GD lib security issues

Hi, I use a fairly standard sort of reseller package (*nix and hsphere based) for hosting sites. Although the versions of php and mySQL are fairly up to date, the version of GD lib is frozen at 1.6.2. When I question my provider about this and when GD v2.x would be available, they replied that there were security issues with GD 2.x in a shared environment and that they wouldn't be offering this version of GD until these had been reviewed and addressed. I haven't had much luck finding out what these issues might be and wondered if anyone else could shed some light on this? Perhaps the right sort of information might help me to encourage them to upgrade. Thanks, verdon