Flash vars and xml

hi all,
i’m having an issue passing flash vars to my externaly loaded swf,
the swf i’m loading will display the flash vars in a dynamic txt feild but it seems as though the xml load command it uses to populate itself cant access them

heres an example

http://www.memedex.com/surveybuilder.php?user_id=3&surveyIdn=62200

you can see the number 3 in the upper left, and bottom right, these are the flash var for the user id, however the xml doesnt seem to get the value since it doesnt populate the movie, and therefore the link is invalid,

var userIdn:Number = _level0.userIdn;
var survey_id:Number = _level0.survey_id;
xml.load(“http://www.memedex.com/api/getsurveyresultsxml.php?user_id="+userIdn+"&survey_id=”+survey_id);

i dont understand how the dynamic text box can read the flash var, but my xml AS cannot.
any help is greatly appriciated.
thanks in advance!