I sparaticly get this error:

Warning: odbc_exec() [function.odbc-exec]: SQL error: [Microsoft][ODBC SQL Server Driver]Communication link failure, SQL state 08S01 in SQLExecDirect in C:\www\inet\phpcc\index.php on line 91
08S01

Some times it happens 5 times in a row than goes away for about 5 pages, I'd say I get it about 50% of the time.

the server has a low load.
Never more than two or three people connected to the server at a time.