Query title starting with a given prefix via WS
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I am using SOAP webservice to retrieve data from Rally platform via Java application.

I would like to get all the user stories (HierarchicalRequirement) whose title starts with a given prefix, lets say title="aaaa - blablabla" and I want to query all the US with title starting with "aaaa". 

Is it possible? Is it possible use regex as parameters for queries?

Thanks in advance!

R.