After upgrading a Grails application from 2.2.0 to 2.2.1 I keep getting the following error when attempting to debug a Grails application from GGTS via Debug as... -> Grails
I had the same problem when running it through eclipse and what worked for me is to make the below changes
Go to Project properties -> Groovy Compiler ->configure workspace settings . Uncheck the checkbox "Enable checking for mismatch between project and workspace groovy compiler levels"