Rules are supposed to be declarative in nature. You should never need to add control statements, neither to the LHS ("when"), nor to the RHS ("then"), although, the RHS being a java code block allows you to do it... but it is usually code smell...
Think about what you are doing and check if you are not trying to use drools as a scripting language...
Following may help:
http://markproctor.blogspot.com/2007/03/writing-better-rules.html
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Edson
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Edson Tirelli
Software Engineer - JBoss Rules Core Developer
Office: +55 11 3529-6000
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