Document for StatusCode(<idc:statuscode) defination in Response XML?

Hi,

Where can I find a document which has definition for different status codes(<idc:statusCode>-64</idc:statusCode>) that appear in the SOAP response?

<SOAP-ENV:Envelope xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/">
<SOAP-ENV:Body>
<idc:CheckInUniversalResponse xmlns:idc="http://www.stellent.com/CheckIn/">
<idc:CheckInUniversalResult>
<idc:dID>59275</idc:dID>
<idc:dRevisionID>1</idc:dRevisionID>
<idc:dRevClassID>59280</idc:dRevClassID>
<idc:dRevLabel>1</idc:dRevLabel>
<idc:StatusInfo>
<idc:statusCode>-64</idc:statusCode>
<idc:statusMessage>Content item &#39;pprd_059280&#39; was not successfully checked in. A value is required for field &#39;Document Type&#39;.</idc:statusMessage>
</idc:StatusInfo>
</idc:CheckInUniversalResult>
</idc:CheckInUniversalResponse>
</SOAP-ENV:Body>
</SOAP-ENV:Envelope>