In the registry:
HKEY_CURRENT_USER\Software\Patchou\Messenger Plus! Live
Change the value of "LanguageFile" (which is a REG_SZ) to "Lng_Turkish.ini".
That will work for the current user. If the current user doesn't still exist, use the following registry path instead:
HKEY_LOCAL_MACHINE\SOFTWARE\Patchou\Messenger Plus! Live
And the name of the key is "DefaultLangFile".
hope that works