kdevelop keeps "forgetting" launch configuration

I'm running kdevelop 4 under ubuntu 10.4. Everything runs fine, except that when I add a launch configuration, the configuration is gone after I've run my project once. The same goes for configuring keyboard shortcuts (except that in this case the changes i made work for just a few seconds). I've run kdevelop 4 from a console to check if some useful information is printed when I do one of the actions mentioned above, but all I got was this:

couldn't lock local file

couldn't lock local file

couldn't 开发者_StackOverflow社区lock local file

Any ideas?