[rules-users] Upgraded Guvnor to 5.1.x from 5.0 and getting expander error with DSL

I just upgraded to the latest milestone and am getting the following error: [package configuration problem][ERR 103] Line 31:0 rule 'rule_key' failed predicate: {(validateIdentifierKey(DroolsSoftKeywords.RULE))}? in rule [package configuration problem][ERR 101] Line 31:9 no viable alternative at input 'TPNOrders' in rule expander [package configuration problem][ERR 101] Line 32:0 no viable alternative at input 'import' in rule expander in rule dsl This exact set of *.brl, *.dsl, drools.package were working up until the upgrade. I've been searching the web but haven't found anything similar. Thanks!