BigDecimal in from accumulate with MVEL with executable-model

import org.drools.modelcompiler.domain.Person;
import java.math.BigDecimal;
global java.util.List list;
dialect "mvel"
rule R when
  $b : BigDecimal() from accumulate (
            Person( $money : money ),
                init( BigDecimal sum = 0; ),
                action( sum += $money; ),
                reverse( sum -= $money; ),
                result( sum )
         )
then
  list.add($b);
end

[ERROR] Failures: 
[ERROR]   AccumulateTest.testFromAccumulateBigDecimalMvel:1273->BaseModelTest.getKieSession:99->BaseModelTest.getKieSession:103->BaseModelTest.getKieContainer:107->BaseModelTest.getKieContainer:114->BaseModelTest.createKieBuilder:125->BaseModelTest.createKieBuilder:152 [Message [id=1, level=ERROR, path=src/main/java/defaultpkg/RAccumulate6.java, line=28, column=20
   text=incompatible types: int cannot be converted to java.math.BigDecimal], Message [id=2, level=ERROR, path=src/main/java/defaultpkg/RAccumulate6.java, line=32, column=18
   text=bad operand types for binary operator '+'
  first type:  java.math.BigDecimal
  second type: java.math.BigDecimal], Message [id=3, level=ERROR, path=src/main/java/defaultpkg/RAccumulate6.java, line=36, column=18
   text=bad operand types for binary operator '-'
  first type:  java.math.BigDecimal
  second type: java.math.BigDecimal], Message [id=4, level=ERROR, path=src/main/java/defaultpkg/RAccumulate6.java, line=0, column=0
   text=Java source of src/main/java/defaultpkg/RAccumulate6.java in error:
package defaultpkg