Hi Sergio,
Got it now, we can specify any valid OGNL expression in property-accessor attribute of property tag. Read a bit about OGNL expressions and got it working.
The below property xml tag is working for me now.
<property property-accessor="arrayToString(testProp)" display-name="Test Property" hidden="false" name="testProp" show-in-column="true" show-in-description="true"/>
Best Regards,
Sumit Tyagi