array key starting with digit ending with string

I have an unusual situation where I have to communicate with an MS based soap server. They have named one of their variables with a name leading with a 1 such as 1variable. Nusoap loads the variable descriptions from the wsdl document and compares the variable names I am trying to send with the ones listed in the wsdl. In this process my sent to the function is something like $data = array('thisvar'=>$myFirstVar,'thatvar'=>$mySecondVar,'1othervar'=>$myLastVar ). Later when the variable names are cycled through on a loop the following test is used... if($data[$currentVarNameInCycle]) { do something } Is there some way force the recognition of the key when it leads with a digit?