Contains Or Index of in

I have been looking for use <s:property> in struts2 if condtion...and I found the solution but Contains or IndexOf doesn't works in my case can someone help me on syntax....

<s:iterator value="DirList" status="DirSTS" var="Dir">
    <s:if test="#DetailsStatus.index==#DirSTS.index">
        <s:if test="%{#Dir.indexOf(':'}!= -1">
            <a href='<s:property/>'><small>Click Here </small></a>
        </s:if>                     
    </s:if>
</s:iterator>

Here DetailsStatus is main list status variable...here I want to check if <s:property> have : symbol