Media Type Script Problem

[Shiva]

Hi
I used a script to ssh to another server that has an ISDN modem and run the sms_client command to send SMS in case of an alert. The action was performed successfully. However, after sometime, no alerts were sent. All actions were in status "Not Sent".
I remove this new media type, restart Zabbix and everything is working fine.
Any pointers what could be wrong? Timeout perhaps?
Running zabbix 1.1.1 on Solaris 10.

Here is the script:

#!/usr/bin/perl
$recipient = $ARGV[0];
$subject = $ARGV[1];
$message = $ARGV[2];
$cmd = "/usr/bin/ssh -l zabbix remoteserver"." "."'"."/usr/bin/sms_client -q $recipient $subject:$message"."'";
$ret = `$cmd`;