The OpenEdge Hive

I am trying to open a URL using webbrowser control by doing a HTTP POST with some xml data to the URL (instead of HTTP GET it normally does). However my code is not working:

DEF VAR wkTarget AS CHAR NO-UNDO.
DEF VAR wkpostData AS INT NO-UNDO.

create "InternetExplorer.Application" chExplorer.
Assign
chExplorer:menubar = false
chExplorer:addressbar = false
chExplorer:toolbar = false no-error.

assign
wkurl = "http://localhost/scripts/cgiip.exe/WService=wsbroker/web/testxml.p"
wkFlags = 0
wkTarget = ""
wkPostData = "somevalue
wkHeaders = "Content-Type: text/xml" +
Chr(10) + Chr(13) +
"Content-Length: " + STRING(LENGTH(wkPostData)) + Chr(10) + Chr(13) +
Chr(10) + Chr(13).

chExplorer:visible = TRUE.
chExplorer:Navigate (wk-url, wkFlags, wkTarget, wkPostData, wkHeaders).

On further enquiry in MSDN I have found that 4th parameter of the nagigate method has to be a SAFEARRAY structure stored in a variable of data type variant. How does one do the same in progress. I tried the following but it is not working either:

DEF VAR mXmlData AS MEMPTR NO-UNDO.
DEF VAR mSafeArray AS MEMPTR NO-UNDO.

ip-Size = LENGTH(wkPostdata).
SET-SIZE(mXmlData) = ip-Size.
PUT-STRING(mXmlData,1) = wkPostData.

SET-SIZE(mSafeArray) = 2 /* WORD cDims */
+ 2 /* WORD fFeatures */
+ 4 /* DWORD cbElements */
+ 4 /* DWORD cLocks */
+ 4 /* void * pvData */
+ 4 /* SAFEARRAYBOUND rgsabound[1] - DWORD cElements */
+ 4 /* SAFEARRAYBOUND rgsabound[1] - LONG lLbound */
.

PUT-SHORT(mSafeArray,1) = 1.
PUT-SHORT(mSafeArray,3) = 0.
PUT-LONG(mSafeArray,5) = 1.
PUT-LONG(mSafeArray,9) = 0.
PUT-LONG(mSafeArray,13) = GET-POINTER-VALUE(mXmlData).
PUT-LONG(mSafeArray,17) = ip-Size.
PUT-LONG(mSafeArray,21) = 0.

ASSIGN
wkFlags = 0
wkTarget = ""
wkPostData = GET-POINTER-VALUE(mSafeArray)
wkHeaders = "Content-Type: text/xml" +
Chr(10) + Chr(13) +
"Content-Length: " + STRING(ip-Size) +
Chr(10) + Chr(13) +
Chr(10) + Chr(13).