There is a patch which has worked for me. The real problem might

be in PQreset, which can't reset a conninfo based connection. The
patch:

Arpad Magosanyi

src/interfaces/libpgtcl/pgtclCmds.c

@@ -7,7 +7,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/interfaces/libpgtcl/Attic/pgtclCmds.c,v 1.25 1998/06/16 04:10:16 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/interfaces/libpgtcl/Attic/pgtclCmds.c,v 1.26 1998/06/16 05:50:55 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -442,7 +442,7 @@ Pg_exec(ClientData cData, Tcl_Interp *interp, int argc, char* argv[])
     else {
 	/* error occurred during the query */
 	Tcl_SetResult(interp, conn->errorMessage, TCL_STATIC);
-	if (connStatus == CONNECTION_OK) {
+	if (connStatus != CONNECTION_OK) {
 	    /* Is this REALLY a good idea?  I don't think so! */
 	    PQreset(conn);
 	    if (conn->status == CONNECTION_OK) {