it does not really help, but I am currently experiencing the same problem. Have you found a way of bypassing it?
Please, submit a bug report.
I have found in the forum a way of solving it: it seems MySQL did not like the removal of the "ADD INDEX" in the template query for checking foreign key (cf the topic "new mysql/innodb foreign key problem in 3.2.2").
I uncommented in META-INF/jbosscmp-jdbc.xml the former MySQL type-mapping for foreign-key constraint and that did it for me.