Tomaz created a jboss-jsp-api_2.2_spec 1.0.x maintenance branch and released 1.0.2 so we could pull it into EAP releases. We should do so for 6.4 to get the fix for bug 1075353.
Upstream tags is https://github.com/jboss/jboss-jsp-api_spec/tree/jboss-jsp-api_2.2_spec-1.0.2.Final
Verified on EAP 6.4.0.ER1