post-earnings conference call might have been reason to "sell in May and go away," Jim Cramer said on


"Stop Trading!" segment Monday.

While headlines emanating from Lehman's second-best quarter ever were positive, the tone of the call was different, with May seeming "horrible," thanks to the

Federal Reserve


Elsewhere, Cramer said rumors are circulating that a big Wall Street firm will turn positive on personal computer stocks such as


(DELL) - Get Report



(INTC) - Get Report

in the next 24 hours, and turn negative on wireless names such as


(NOK) - Get Report


Texas Instruments

(TXN) - Get Report


RF Micro


. Cramer said he belives the momentum is still in wireless but wanted to pass along the tip.

Houston Exploration


looks cheap the same way





(MRO) - Get Report

previously were.

"People are dumping stocks at six times earnings, I guess they think they're going to three times earnings. History shows that that is a fool's bet," Cramer said.

At the time of publication, Cramer had no position in the stocks mentioned.

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