[Soot-list] "Duplicate class" error

[The Hung Dao]

I run Soot inlining for JFlex and I have this error:
production_part.java:13-94: Duplicate class "java_cup.production_part".
compilation failed: Could not compile

What does it mean and how to fix?

PS: I turned off all option except Call graph option. I type this command:
java soot.Main --app -w -debug-resolver -process-dir C:\JFlex -src-prec java
-main-class JFlex/Main -full-resolver -p jb off -p jj off -p cg
verbose:true,jdkver:4,trim-clinit:false -p cg.cha enabled:true -p wstp
enabled:false -p wsop enabled:false -p wjtp enabled:false -p
wjop.smbenabled:false -p
wjop.si enabled:false,expansion-factor:5 -p wjap enabled:false -p shimple
enabled:false -p stp enabled:false -p sop enabled:false -p jtp enabled:false
-p jop enabled:false -p jap enabled:false -p gb enabled:false -p gop
enabled:false -p bb enabled:false -p bop enabled:false -p tag enabled:false
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://mailman.CS.McGill.CA/pipermail/soot-list/attachments/20060411/df6f48ff/attachment.htm