I 've never tried to deploy the jBPM console to tomcat...I deploy it in jBoss AS 5.1 (instead of AS7) and I can say that it's not so immediate (there are a couple of files to be modified)...
For sure, you have to check all the dependencies..jboss as comes with lot of libraries jbpm needs (like hibernate) while tomcat doesn't..so you need to add all thoose libraries to your tomcat (or put them in the application webinf/lib)
Then you have to check the datasource needed by the console and add it to your tomcat...