diff --git a/main.c b/main.c
index 02fc23e..7a0a2e6 100644
--- a/main.c
+++ b/main.c
@@ -1,7 +1,7 @@
 /*****************************************************************************
 *
 * AVRPROG compatible boot-loader
-* Version  : 0.83 (Apr. 2008)
+* Version  : 0.85 (Dec. 2008)
 * Compiler : avr-gcc 4.1.2 / avr-libc 1.4.6
 * size     : depends on features and startup ( minmal features < 512 words)
 * by       : Martin Thomas, Kaiserslautern, Germany
@@ -149,6 +149,15 @@
 #define GET_EXTENDED_FUSE_BITS  0x0002
 
 
+#ifdef UART_DOUBLESPEED
+// #define UART_CALC_BAUDRATE(baudRate) (((F_CPU*10UL) / ((baudRate) *8UL) +5)/10 -1)
+#define UART_CALC_BAUDRATE(baudRate) ((uint32_t)((F_CPU) + ((uint32_t)baudRate * 4UL)) / ((uint32_t)(baudRate) * 8UL) - 1)
+#else
+// #define UART_CALC_BAUDRATE(baudRate) (((F_CPU*10UL) / ((baudRate)*16UL) +5)/10 -1)
+#define UART_CALC_BAUDRATE(baudRate) ((uint32_t)((F_CPU) + ((uint32_t)baudRate * 8UL)) / ((uint32_t)(baudRate) * 16UL) - 1)
+#endif
+
+
 #include <stdint.h>
 #include <avr/io.h>
 #include <avr/wdt.h>
@@ -367,6 +376,9 @@ int main(void)
 		if ((BLPIN & (1<<BLPNUM))) {
 			// jump to main app if pin is not grounded
 			BLPORT &= ~(1<<BLPNUM);	// set to default
+#ifdef UART_DOUBLESPEED
+			UART_STATUS &= ~( 1<<UART_DOUBLE );
+#endif
 			jump_to_app();		// Jump to application sector
 
 		} else {
@@ -392,7 +404,10 @@ int main(void)
 
 	if ((BLPIN & (1<<BLPNUM))) {
 		// jump to main app if pin is not grounded
-		BLPORT &= ~(1<<BLPNUM);		// set to default
+		BLPORT &= ~(1<<BLPNUM);		// set to default		
+#ifdef UART_DOUBLESPEED
+		UART_STATUS &= ~( 1<<UART_DOUBLE );
+#endif
 		jump_to_app();			// Jump to application sector
 	}
 
diff --git a/mega128.h b/mega128.h
index 800501d..a8f148c 100644
--- a/mega128.h
+++ b/mega128.h
@@ -10,13 +10,6 @@
 #define SIG_BYTE2	0x97
 #define SIG_BYTE3	0x02
 
-
-#ifdef UART_DOUBLESPEED
-#define UART_CALC_BAUDRATE(baudRate) ((uint32_t)(F_CPU) / ((uint32_t)(baudRate) *8) -1)
-#else
-#define UART_CALC_BAUDRATE(baudRate) ((uint32_t)(F_CPU) / ((uint32_t)(baudRate)*16) -1)
-#endif
-
 #ifndef UART_USE_SECOND
 #define UART_BAUD_HIGH	UBRR0H
 #define UART_BAUD_LOW	UBRR0L
diff --git a/mega128can.h b/mega128can.h
index a57b73d..08f6a0d 100644
--- a/mega128can.h
+++ b/mega128can.h
@@ -13,12 +13,6 @@
 #define SIG_BYTE3	0x81
 
 
-#ifdef UART_DOUBLESPEED
-#define UART_CALC_BAUDRATE(baudRate) ((uint32_t)(F_CPU) / ((uint32_t)(baudRate) *8) -1)
-#else
-#define UART_CALC_BAUDRATE(baudRate) ((uint32_t)(F_CPU) / ((uint32_t)(baudRate)*16) -1)
-#endif
-
 #ifndef UART_USE_SECOND
 #define UART_BAUD_HIGH	UBRR0H
 #define UART_BAUD_LOW	UBRR0L
diff --git a/mega16.h b/mega16.h
index 533d7a9..0c0bbe1 100644
--- a/mega16.h
+++ b/mega16.h
@@ -10,13 +10,6 @@
 #define SIG_BYTE2	0x94
 #define SIG_BYTE3	0x03
 
-
-#ifdef UART_DOUBLESPEED
-#define UART_CALC_BAUDRATE(baudRate) ((uint32_t)(F_CPU) / ((uint32_t)(baudRate) *8) -1)
-#else
-#define UART_CALC_BAUDRATE(baudRate) ((uint32_t)(F_CPU) / ((uint32_t)(baudRate)*16) -1)
-#endif
-
 #define UART_BAUD_HIGH	UBRRH
 #define UART_BAUD_LOW	UBRRL
 #define UART_STATUS	UCSRA
diff --git a/mega162.h b/mega162.h
index 57a107b..c2e30bb 100644
--- a/mega162.h
+++ b/mega162.h
@@ -16,13 +16,6 @@
 #define SIG_BYTE2	0x94
 #define SIG_BYTE3	0x04
 
-
-#ifdef UART_DOUBLESPEED
-#define UART_CALC_BAUDRATE(baudRate) ((uint32_t)(F_CPU) / ((uint32_t)(baudRate) *8) -1)
-#else
-#define UART_CALC_BAUDRATE(baudRate) ((uint32_t)(F_CPU) / ((uint32_t)(baudRate)*16) -1)
-#endif
-
 #ifndef UART_USE_SECOND
 #define UART_BAUD_HIGH     UBRR0H
 #define UART_BAUD_LOW      UBRR0L
diff --git a/mega169.h b/mega169.h
index 4c33806..27918e1 100644
--- a/mega169.h
+++ b/mega169.h
@@ -8,13 +8,6 @@
 #define SIG_BYTE2	0x94
 #define SIG_BYTE1	0x05
 
-
-#ifdef UART_DOUBLESPEED
-#define UART_CALC_BAUDRATE(baudRate) ((uint32_t)(F_CPU) / ((uint32_t)(baudRate) *8) -1)
-#else
-#define UART_CALC_BAUDRATE(baudRate) ((uint32_t)(F_CPU) / ((uint32_t)(baudRate)*16) -1)
-#endif
-
 #define UART_BAUD_HIGH	UBRRH
 #define UART_BAUD_LOW	UBRRL
 #define UART_STATUS	UCSRA
diff --git a/mega32.h b/mega32.h
index 5827e92..b09db16 100644
--- a/mega32.h
+++ b/mega32.h
@@ -10,13 +10,6 @@
 #define SIG_BYTE2	0x95
 #define SIG_BYTE3	0x02
 
-
-#ifdef UART_DOUBLESPEED
-#define UART_CALC_BAUDRATE(baudRate) ((uint32_t)(F_CPU) / ((uint32_t)(baudRate) *8) -1)
-#else
-#define UART_CALC_BAUDRATE(baudRate) ((uint32_t)(F_CPU) / ((uint32_t)(baudRate)*16) -1)
-#endif
-
 #define UART_BAUD_HIGH	UBRRH
 #define UART_BAUD_LOW	UBRRL
 #define UART_STATUS	UCSRA
diff --git a/mega64.h b/mega64.h
index e84e786..954915d 100644
--- a/mega64.h
+++ b/mega64.h
@@ -10,13 +10,6 @@
 #define SIG_BYTE2	0x96
 #define SIG_BYTE3	0x02
 
-
-#ifdef UART_DOUBLESPEED
-#define UART_CALC_BAUDRATE(baudRate) (((F_CPU*10UL) / ((baudRate) *8UL) +5)/10 -1)
-#else
-#define UART_CALC_BAUDRATE(baudRate) (((F_CPU*10UL) / ((baudRate)*16UL) +5)/10 -1)
-#endif
-
 #ifndef UART_USE_SECOND
 #define UART_BAUD_HIGH	UBRR0H
 #define UART_BAUD_LOW	UBRR0L
diff --git a/mega644.h b/mega644.h
index 052a745..0926944 100644
--- a/mega644.h
+++ b/mega644.h
@@ -12,13 +12,6 @@
 #define SIG_BYTE2	0x96
 #define SIG_BYTE3	0x09
 
-
-#ifdef UART_DOUBLESPEED
-#define UART_CALC_BAUDRATE(baudRate) ((uint32_t)(F_CPU) / ((uint32_t)(baudRate) *8) -1)
-#else
-#define UART_CALC_BAUDRATE(baudRate) ((uint32_t)(F_CPU) / ((uint32_t)(baudRate)*16) -1)
-#endif
-
 #define UART_BAUD_HIGH	UBRR0H
 #define UART_BAUD_LOW	UBRR0L
 #define UART_STATUS	    UCSR0A
diff --git a/mega8.h b/mega8.h
index 33420c8..d101c97 100644
--- a/mega8.h
+++ b/mega8.h
@@ -10,13 +10,6 @@
 #define SIG_BYTE2	0x93
 #define SIG_BYTE3	0x07
 
-
-#ifdef UART_DOUBLESPEED
-#define UART_CALC_BAUDRATE(baudRate) ((uint32_t)(F_CPU) / ((uint32_t)(baudRate) *8) -1)
-#else
-#define UART_CALC_BAUDRATE(baudRate) ((uint32_t)(F_CPU) / ((uint32_t)(baudRate)*16) -1)
-#endif
-
 #define UART_BAUD_HIGH	UBRRH
 #define UART_BAUD_LOW	UBRRL
 #define UART_STATUS	UCSRA
diff --git a/megaxx4p.h b/megaxx4p.h
index feffab8..635eaf7 100644
--- a/megaxx4p.h
+++ b/megaxx4p.h
@@ -1,12 +1,6 @@
 #ifndef _MEGAxx4_H_
 #define _MEGAxx4_H_
 
-#ifdef UART_DOUBLESPEED
-#define UART_CALC_BAUDRATE(baudRate) ((uint32_t)(F_CPU) / ((uint32_t)(baudRate) *8) -1)
-#else
-#define UART_CALC_BAUDRATE(baudRate) ((uint32_t)(F_CPU) / ((uint32_t)(baudRate)*16) -1)
-#endif
-
 #ifndef UART_USE_SECOND
 /* UART 0 */
 #define UART_BAUD_HIGH	UBRR0H
diff --git a/readme.txt b/readme.txt
index c36f6fc..e1af4e3 100644
--- a/readme.txt
+++ b/readme.txt
@@ -30,6 +30,12 @@ Programming-Software (on the "PC-Side"):
 * Installation instructions at the end of this file.
 
 
+3. Dec. 2008 - Version 0.85
+
+* disable U2X before jump to app as suggested be Alexander Döller
+* moved UBRR-macros to main.c and changed them. Inspired by code from avr-libc setbaud.
+  (macros which are commented out (//) are from Pavel Fertser)
+
 6. Nov. 2008 - Version 0.84
 
 * Added definitions for ATmega64 provided by Pavel Fertser - Thanks.