This is the most frequently requested feature on kmeleon. I am using third party programs to use tabbed interface for kmeleon.
Use Scope (400kb. freeware to make tabbed interface for browsers)
You will need mozctlx.dll (40kb) from mozilla. Put this in your k-meleon directory.Open a DOS prompt, change to your kmeleon directory (e.g. "cd c:\Program Files\k-meleon\"). Type "regsvr32 mozctlx.dll". Thats it you can use kmeleon as a tabbed browser inside scope.
Use wintabs (tabbed interface for windows)
(works only with kmeleon 0.4)