Global AST doesn't seem to work

I've tried to add log_code_guard.jar to the project classpath (the whole global AST is written in pure Java), but it wasn't enough. Am i missing something? It seems nothing is going on...

If i try to run using the command line, it "works" (i've inserted a bug
to be sure that the transformation was happening):

[daniel@anyhost test_log]$ groovy
-cp ./lib/log4j-1.2.15.jar:./lib/log_code_guard.jar:./bin
src/Bla.groovy
visitClass(): node Bla
log exp: LOGGER.debug(ok)
log method: debug
log method enabled: isDebugEnabled
parent if null
replacing...
1
Caught: groovy.lang.MissingMethodException: No signature of method:
org.apache.log4j.Logger.isDebugEnabled_() is applicable for argument
types: () values: []
Possible solutions: isDebugEnabled()
at Bla.main(Bla.groovy:9)

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Thread:

http://markmail.org/message/sb4greb5vorpgcif?q=global+ast+list:org%2Ecodehaus%2Egroovy%2Eeclipse-plugin-user