FM8 create relative Path

Here is the read write rule I am using:

element "graphic"
{
is fm graphic element;
attribute "entity" drop;
attribute "boardno" is fm property file;

}

This is the output:

<graphic
    boardno = "file:///H:/My%20Documents/IMS/IMS%20CURRENT%20DEVELOPMENT/Frame%20Docs /graphics/ims_system.jpg"></graphic>

The output I wish is

<graphic boardno = "graphics/ims_system.jpg"></graphic>

Any Suggestions?