Latinnews.com ($) reports:

On 22 May the Instituto Federal Electoral (IFE) fined all the registered political parties varying sums for failing to follow the rules in the 2006 elections.

The fines were nothing like those dished out after the 2000 elections when the defeated Partido Revolucionario Institucional was crippled after it was convicted of trying to use money from the state oil company Pemex to pay for election expenses. Then the PRI on its own was fined over M$900m (US$92m). For the 2006 elections the total fines on all the parties came to M$99m (US$9m). 

…The IFE may issue further fines because it still has not discovered who paid for 281,026 radio and TV adverts that were broadcast during the election. The president of the IFE, Luis Carlos Ugalde, said that 70% of the election expenses went on broadcasting but it was unclear in 37% of the cases who paid for what. 

The report does not say which laws were violated by the parties.