Here is the latest version of MyRolePlay — 3.0.51, compatible with WoW 3.1.3.9947.
http://moonshyne.org/MyRolePlay-3.0.51.zip (157KB; ZIP archive)
As always, I recommend you back up your WTF folders before upgrading, especially from an older version, but this should function correctly. Hopefully there won't be too many problems anymore.

MyRolePlay 3.0.51 is backwards-compatible back to MyRolePlay Beta 3.0.48, and cross-compatible with FlagRSP-TBC, FlagRSP2, ImmersionRP.
If anyone's using an old MyRolePlay version, particularly older than Beta 3.0.48, it's time to bug them to update to this one, because old versions don't work properly anymore! ^^
Changelog3.0.51- EM: Removed nearly all of the debug spam by default; you no longer see a list of all the people in the MRP/FlagRSP channels when you log in. (If you're still curious, open the Chat panel and have a look, or enable MRP_DEBUG in MyRolePlay.lua.)
- EM: NPCs with the same name as a player will no longer confuse MyRolePlay.
3.0.50- EM: Bumped to TOC 30100.
- EM: Increased idle timeout further for channel joining to 180s (up from 120s).
- EM: Reduced rate of channel messages further, to a max of one every 0.4 seconds (up from 0.25s) to reduce chat lag.