I do not believe I’ve seen this error before. A quick Google search led me to this page (and many more like it)
Seems it is a server configuration item. Please try the solutions provided in the above link. You web host should also be able to help you with this.
Let me know how it goes.
ps. There have been no significant change in how Connections saves and entry in ages. If fact it simply uses the WordPress DB API, nothing fancy — so to speak.