We have the same problem here. Today it was the second time, that MyEclipse did not start and I had to completely reinstall MyEclipse to get it back working. My eclipse.ini by default contains the above configurations so this does not solve the problem. I also tried the -clean option but it did not work.
Maybe the problem has to do with the Matisse editor. Because in both cases I was working with GUI programming before the problem occured the next time I tried to start MyEclipse.