Those who feel that even wee Gary Coleman, for all his unchecked adorability, is still insufficiently cute may find the new ABC sitcom "Webster," premiering at 8:30 tonight on Channel 7, just their cup of yech. A shameless steal from NBC's "Diff'rent Strokes," the show in which Coleman plays one of two black orphans adopted by a white Park Avenue millionaire, "Webster" brings to series television Emmanuel Lewis, previously the star of commercials for Jell-O pudding and Burger King fast-food restaurants.

Lewis plays the suddenly orphaned son of a football player, one Peanut Butter Bukowski, whose teammate, played in the series by Alex Karras, promised in a weak moment to look after the tyke should anything fatal befall Mr. Peanut. In the premiere, however, much time is wasted by writer Stu Silver establishing the characters played by Karras and, as his new bride, his real-life wife Susan Clark, who grows increasingly hard and unappealing with each successive TV performance, while Karras grows more and more the sheepish simp.

When they arrive in the woman's apartment, back from a two-week newlyweds' cruise of Greece, the couple fritters time away on wan gags and stale innuendo. The situation is made worse with the arrival of her personal secretary (played by Henry Polic II) who also decorated the apartment and appears to be gay. Hollywood happily caters to the notion that all homosexual men are swish interior decorators at heart.

Finally, the kid arrives, but he doesn't get a single line in the first act; in fact, he is barely on the scene when he decides to run away, because he hears the couple, especially the woman, expressing anxiety about raising him as their own son. Eventually Karras tracks the kid down to Soldier Field (the series is set in Chicago) and in a closing scene, Clark shakes hands goodnight with him. It's about as tender and sweet as a memo from David Stockman.

The child is certainly telegenic, but the pilot seems to have been taped on the day all his baby teeth fell out. He can barely enunciate, much less put over knee-slappers in socko style. As for Karras, he appears determined to humiliate himself as often as possible by playing weak, emasculated characters; his gentle giant routine is so worn now that it's nearly appalling. He whimpers and shuffles as though apologizing for being alive.

Again, "Webster" supports the network credo that a series can have a black lead so long as the character is a cute child, a silly adult, or a subordinated lackey. Not a pretty picture. But even discounting such sad facts of life, "Webster" the show, like Webster the killer tot, seems very much a lost child looking for a home, or at least a good script.