infoContent JavaScript error

System

Opening an existing DCR using a CCI link, I sometimes (haven't figured out the pattern) get the attached error. Debugging shows that this is from the “open()” call in this line of code:

function setInfoFrameHTML( html )
{
//Write the html to the document.
infoContent.document.open();
infoContent.document.write( html );
infoContent.document.close();
}

This function is apparently defined in datacapture_info_frame.jsp (I can send the entire source of this frame if needed, but this line seems to be the first reference to this object). I never use a variable of this name in my FormAPI so I don’t think there’s a conflict. Does anyone know what could be causing this?