With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
cGgsnVersion
Cisco Ggsn Version
1.3.6.1.4.1.9.9.240.1.4.1
This object specifies the which release of GPRS image is currently running on the GGSN.
Back to CISCO-GGSN-MIB MIB page.
IPHost Network monitor allows you to monitor cGgsnVersion on Cisco device via the SNMP protocol. Download IPHost Network Monitor (500 monitors for 30 days, 50 monitors free forever) to start monitoring Cisco wireless switches right now.