PGTYPEStimestamp_sub should use the values and not the pointers to substract.

src/interfaces/ecpg/ChangeLog

@@ -2341,6 +2341,11 @@ Wed, 26 Mar 2008 17:02:08 +0100
 
 	- Moved from PQsetdbLogin to PQconnectDB.
 	- Correctly parse connect options.
+
+Thu, 10 Apr 2008 12:42:25 +0200
+
+	- Fixed bug in PGTYPEStimestamp_sub that used pointers instead of the
+	  values to substract.
 	- Set pgtypes library version to 3.1.
 	- Set compat library version to 3.1.
 	- Set ecpg library version to 6.2.

src/interfaces/ecpg/pgtypeslib/timestamp.c

@@ -867,7 +867,7 @@ PGTYPEStimestamp_sub(timestamp * ts1, timestamp * ts2, interval * iv)
 	if (TIMESTAMP_NOT_FINITE(*ts1) || TIMESTAMP_NOT_FINITE(*ts2))
 		return PGTYPES_TS_ERR_EINFTIME;
 	else
-		iv->time = (ts1 - ts2);
+		iv->time = (*ts1 - *ts2);
 
 	iv->month = 0;