Apparently the recent comeback of the Q2-legend Shub_Nigga was too good to be true as it turned out to be the known cheater Yuka.

Loosely translated from the Swedish site Rakaka.se:
"Shub_nigga was a fake

A few days ago Rakaka.se reported that the Q2-legend Shub_Nigga had come back to the spotlight and Quake Live. Shub had joined pstarz where, amongst others, Quake star Cooller playes TDM. The team also won their first match against top seeded LLL.

The truth has come to light about "Shub_Nigga".
Alot of people were saying on both the comment section and IRC that this probably was a fake. One thing that stood out was that Shub didn't know any Swedish, although he is Norwegian. These accusations have now shown their selves to be true.

Shub_Nigga was really another player called Yuka, who have been caught cheating in the past.
Apparently it was a known cheater who has previously played in k1ck (where some Swedes also play) by the name Yuka who had started calling himself Shub. This worked so well that he managed to trick the whole pstarz clan. ESL havn't had a clue about this since pstarz still remain the victor over LLL in the ESM QL TDM.

id Softwares Community Manager, SyncError, caught the impostor.
After being asked by some known Quake profiles SyncError chose to check this Shub_nigga via IP tracking, and it turned out to be the already banned Yuka."

When I asked SyncError on IRC about his method on finding out it was actually Yuka playing he said:
"Several players (around a dozen) had reported shub_nigga in the past few days. Claims that he neither knew his native tongue and that his play style was different.
They believed him to be another player who was already actively playing on another team. I looked into the claims and after following a few trails from the account information found that yuka had obtained a new ip address and registered the account 'shub_nigga' on Nov 2nd.
I then spoke with yuka on irc and he confirmed that he was playing under the alias.
The account is currently banned."

Source: Rakaka.se - SyncError (id Software community manager)