diff --git a/jtag/ChangeLog b/jtag/ChangeLog
index 8e390d5b..f010d32d 100644
--- a/jtag/ChangeLog
+++ b/jtag/ChangeLog
@@ -1,5 +1,8 @@
 2009-03-28  Arnim Laeuger  <arniml>
 
+  * src/tap/chain.c (chain_set_pod_signal) : keep old value of trst in
+    case trst isn't modified by mask/val
+
   * src/tap/chain.c: [ 2610857 ] chain_set_pod_signal() looks funky
 
   * UrJTAG.txt: typo
diff --git a/jtag/src/tap/chain.c b/jtag/src/tap/chain.c
index 6b94b43f..76ae7984 100644
--- a/jtag/src/tap/chain.c
+++ b/jtag/src/tap/chain.c
@@ -122,7 +122,7 @@ chain_set_pod_signal( chain_t *chain, int mask, int val )
 {
 	int old_val = cable_set_signal( chain->cable, mask, val );
 	int old_trst = (old_val & CS_TRST) ? 1 : 0;
-	int new_trst = (val & mask & CS_TRST)  ? 1 : 0;
+	int new_trst = (((old_val & ~mask) | (val & mask)) & CS_TRST) ? 1 : 0;
 	tap_state_set_trst( chain, old_trst, new_trst );
 	return old_val;
 }