variable doesn't work for version

[Raghu]

I have a POM with parent node as below: <parent> <groupId>com.test</groupId> 
<artifactId>pom.parent</artifactId> <version>${test.version}</version> 
<relativePath>../scripts/pom.xml</relativePath> </parent>
This used to work till maven 3.3.3 version - mvn clean install. However, the 
version 3.3.9 throws error though. When I change the version to a value instead 
of the variable, it works fine.
Won't maven support variable for version? Or is it a bug with 3.3.9?
Appreciate your response...
- regards,raghu