PHP5 SOAP not adding namespace to parameters

Dear all,

we're having a problem with the SOAP extension provided by PHP5. Similar
calls using the SOAP component of PEAR work.

Tracing the request with a network analyzer this is what PHP5 generates:

<SOAP-ENV:Envelope
xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/"
xmlns:ns1="TCOL_MATRIX">
<SOAP-ENV:Body>
<ns1:Addr_Map>
<reg></reg>
<prov>mi</prov>
<com>milano</com>
<fraz></fraz>
<topo>Cuoco</topo>
<civ>7</civ>
<gst></gst>
</ns1:Addr_Map>
</SOAP-ENV:Body>
</SOAP-ENV:Envelope>

This is what PEAR generates:

<SOAP-ENV:Envelope
xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/"
xmlns:xsd="http://www.w3.org/2001/XMLSchema"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:SOAP-ENC="http://schemas.xmlsoap.org/soap/encoding/"
xmlns:ns4="TCOL_MATRIX">
<SOAP-ENV:Body>
<ns4:Addr_Map>
<ns4:reg></ns4:reg>
<ns4:prov>mi</ns4:prov>
<ns4:com>milano</ns4:com>
<ns4:fraz></ns4:fraz>
<ns4:topo></ns4:topo>
<ns4:civ></ns4:civ>
<ns4:gst></ns4:gst>
</ns4:Addr_Map>
</SOAP-ENV:Body>
</SOAP-ENV:Envelope>


Why doesn't PHP5 add the "ns4" namespace to the parameters ? Is there a
way to force it to ?

Thanks

Tristan