See this statement from FINA:

“Following reports on the media referring the participation of Mr. Lance Armstrong in the Masters South Central Zone Swimming Championships in Texas (USA), FINA would like to clarify that:

1. This national competition is under the jurisdiction of the US Masters Swimming; 
2. FINA Rule DC 15.1 states: 

“Subject to the right to appeal provided in DC 13, the Testing, therapeutic use exemptions and hearing results or other final adjudications of any Signatory to the Code which are consistent with the Code and are within the Signatory’s authority, shall be recognised and respected by FINA and its Member Federations.(…)”

Therefore, FINA wrote a letter to the US Masters Swimming (with copy to US Aquatic Sports and USA Swimming) requesting not to accept the entry of Mr. Lance Armstrong in the above mentioned competition.”