The second live "30 Rock" episode aired Thursday night and though the episode was performed without a hitch, one moment in particular is causing raised eyebrows all over the Internet: Jon Hamm's blackface cameo.

The plot of the episode, "Live From Studio 6H," involved NBC page Kenneth (Jack McBrayer) explaining the history and value of live TV to the cast and writers of "TGS," including Liz Lemon (Tina Fey) and Tracy Jordan (Tracy Morgan). Intercut with his explanations were "clips" from the various live shows from the network's history. One of those shows was an "Amos 'n Andy"-style show called "Alfie and Abner" starring Morgan and Hamm, with Hamm appearing in blackface.

The bit pointed out the unfortunate TV history of hiring white actors to play black characters, with Morgan's Alfie expressing increasing disgust at his co-star's buffoonish performance. The gag seems to have been the most notable thing about the live episode -- with people either praising Hamm as the best thing about the show, or condemning the bit for trafficking in racist humor.

Truthbesold tweeted, "I believe Tina Fey is a racist morally repugnant socially insensitive culturally incompetent bigot I'm done@30rock jon hamm #blackface."

Cornelius Jemison tweeted, "Blackface isn't funny."

Nodnerb B. tweeted, "Jon Hamm in blackface?! #DEAD. #30Rock . I cannot.

Zig Me tweeted, "And now we have Jon Hamm is blackface (sort of) making fun of blackface (sort of). I don't know how to feel about this."

However, the scene did have its fans.

Derrick tweeted, "Whoa, was that #JonHamm in pseudo-Blackface doing the Amos & Andy parody? Funny! And a bit uncomfortable."

Chris Gannon tweeted, "You wouldn't think blackface could be funny in 2012 but there's Jon hamm to prove everyone wrong."

Andrew Shaw tweeted, "Jon Hamm in blackface on 30 Rock Live is now my favourite thing in the universe. #BANJO."

Andrew Davis tweeted, "member when Jon Hamm was in blackface on 30 Rock? That was awesome."

Russell Johnson tweeted, "The Tracy Morgan and John Hamm blackface bit may be the best gag ever done on the entire show's run. Watch the cast try to hold back laughs."

The live show was performed twice, for the East and West coasts, and though the Hamm and Morgan scene was performed the same both times, there were many differences between the two airings.

On the East Coast, viewers got a surprise cameo by Paul McCartney. On the West Coast, it was Kim Kardashian. On the East Coast, Hamm also portrayed a sexist version of late NBC newsman David Brinkley. On the West Coast, Brian Williams took the sexist anchor spot.

Though Thursday's live "30 Rock" episode drew better ratings compared with recent weeks, it didn't surpass last season's live episode, which drew 6.7 million viewers.

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-- Patrick Kevin Day

Photo: Jon Hamm, left, and Tracy Morgan in "30 Rock." Credit: NBC