The article speaks first about TIFF files then follows up with an update from a conversation with the security hacker concerning PNG files. There are two exploits - PNG files, which is fixed by applying 4.0 SP3, and TIFF files, which is still an open issue.
US-CERT Advisory:
http://www.kb.cert.org/vuls/id/570768
RIM KB Article for TIFF:
http://www.blackberry.com/knowledgec...nodeid=1167895
RIM KB Article for PNG:
http://www.blackberry.com/knowledgec...nodeid=1167794