diff --git a/ChangeLog b/ChangeLog
index 58d33bb2..4343b9fa 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+2004-07-04  Jan-Hinnerk Reichert  <hinni@despammed.com>
+	* stk500.c: Fixed fosc behaviour for values exceeding
+	maximum frequency (contributed by Galen Seitz)
+
 2004-07-04  Jan-Hinnerk Reichert  <hinni@despammed.com>
 	* avrdude.conf.in: Added support for
         ATtiny2313 (contributed by Bob Paddock)
diff --git a/stk500.c b/stk500.c
index dba06a85..ff232fda 100644
--- a/stk500.c
+++ b/stk500.c
@@ -919,7 +919,7 @@ static int stk500_set_fosc(PROGRAMMER * pgm, double v)
       if (fosc >= fbase / (256 * ps[idx] * 2)) {
         /* this prescaler value can handle our frequency */
         prescale = idx + 1;
-        cmatch = (unsigned)(fbase / (2 * v * ps[idx]));
+        cmatch = (unsigned)(fbase / (2 * fosc * ps[idx])) - 1;
         break;
       }
     }