Eclipse CDT -不能打开编辑器:编辑器无法初始化?

I'm running Eclipse Helios (3.6) with the latest CDT (plus HgEclipse, ANTLR IDE, PDT, and probably a few other things). It was running great, until recently in which when I tried to open any file that uses the C/C++ editor in CDT gives an error:I'm running Eclipse Helios (3.6) with the lates