NT Registry key to limit program instances

[Berkhan, Sharon .]

Our public NT workstations use Netscape for the browser, and we've locked it
down pretty well using WinSelect and NT policies.  What we're having trouble
finding is a way to limit the number of instances of Netscape to just 1, so
patrons can't open additional Netscape windows.  Does anyone know what
registry entry this is controlled by and what the value should be?  I've
searched the archives but haven't found anything on this.  

Thanks,

Sharon Berkhan
Manager, Systems & Telecommunications
Minneapolis Public Library
300 Nicollet Mall
Minneapolis, MN  55401
Voice: 612-630-6401
Fax: 612-630-6435
sberkhan at mpls.lib.mn.us