Curl request works on command line but not in script

Hi folks, I'm trying to send an XML request to a server to get its response back... I can get it to work on the command line (with passthru) but not with libcurl. I'm using libcurl 7.9.2 which may actually be different from the curl on the command line... the latter came with OS X, the former came from entropy.ch with the PHP package I installed. Of course my host is using 7.9.4 and the script doesn't work there either. I've tried it with both GET and POST... here are some setup variables. $testrequest = "$server?API=Rate&XML=<RateRequest USERID=\"$userid\" PASSWORD=\"$password\"><Package ID=\"0\"><Service>EXPRESS</Service><ZipOrigination>20770</ZipOrigination><ZipDestination>20852</ZipDestination><Pounds>10</Pounds><Ounces>0</Ounces><Container>None</Container><Size>REGULAR</Size><Machinable></Machinable></Package></RateRequest>"; $post['API']="Rate\n"; $post['XML']= "'<RateRequest USERID=\"$userid\" PASSWORD=\"$password\"><Package ID=\"0\"><Service>EXPRESS</Service><ZipOrigination>20770</ZipOrigination><ZipDestination>20852</ZipDestination><Pounds>10</Pounds><Ounces>0</Ounces><Container>None</Container><Size>REGULAR</Size><Machinable></Machinable></Package></RateRequest>'\n"; # (I've tried it with the 's and without, with the \n's and without) $d1 = "API=Rate"; $d2 = "XML='<RateRequest USERID=\"$userid\" PASSWORD=\"$password\"><Package ID=\"0\"><Service>EXPRESS</Service><ZipOrigination>20770</ZipOrigination><ZipDestination>20852</ZipDestination><Pounds>10</Pounds><Ounces>0</Ounces><Container>None</Container><Size>REGULAR</Size><Machinable></Machinable></Package></RateRequest>'"; $ch = curl_init(); # doesn't work, returns Error 400 curl_setopt($ch, CURLOPT_URL, $testrequest); # also doesn't work, returns BAD REQUEST curl_setopt($ch, CURLOPT_URL, $server); curl_setopt($ch,CURLOPT_POSTFIELDS,$post); # what DOES work passthru("curl -d " . $d1 . " -d " . $d2 . " $server"); Any ideas? -Josh