I previously used version 1.0.1 OpenVPN released their new version 1.0.2 Dec 16. After the download, the install almost finishes and then a dialog box puts up saying it can't be installed at this time. The dialog box then gives the options "Done" & "Retry". At this time, the original version is unusable.
According to the OpenVPN support forums,
forums.openvpn.net/topic14552 this is now a known issue and they have forwarded the issue to Apple. There is a bug with 5.1.1 IOS that is interfering with the new software for the new 32 and 64 bit platforms.
So until they come up with a new solution or I find a different VPN client, I'm out of luck with my Ipad