Current Lynx versions can optionally support HTTP POST;
however, it doesn't work for the PHP file upload functions.
I believe this happens because the upload might be broken in the RFC, but I've seen some discussion on the site http://www.flora.org/lynx-dev/html/month082000/msg00087.html that suggests PHP3 uploads were broken with lynx. 

I'm attaching the (edited and ^Med) POST produced so somebody who knows the RFC better can comment:

POST / HTTP/1.0
Host: blackjesus
Accept: text/html, text/plain, audio/x-pn-realaudio, audio/vnd.rn-realaudio, application/smil, text/vnd.rn-realtext, video/vnd.rn-realvideo, image/vnd.rn-realflash, application/x-shockwave-flash2-preview, application/sdp, application/x-sdp
Accept: application/vnd.rn-realmedia, image/vnd.rn-realpix, audio/wav, audio/x-wav, audio/x-pn-wav, audio/x-pn-windows-acm, audio/basic, audio/x-pn-au, audio/aiff, audio/x-aiff, audio/x-pn-aiff, text/sgml, video/mpeg, image/jpeg, image/tiff
Accept: image/x-rgb, image/png, image/x-xbitmap, image/x-xbm, image/gif, application/postscript, */*;q=0.01
Accept-Encoding: gzip, compress
Accept-Language: en
Pragma: no-cache
Cache-Control: no-cache
User-Agent: Lynx/2.8.4rel.1 libwww-FM/2.14 SSL-MM/1.4.1 OpenSSL/0.9.6
Referer: http://www.async.com.br/hireme.phpc2ggQ29taWNzPC9BPgo8L0RMPjxwPgo=
^M
--xnyLAaB03X^M
Content-Disposition: form-data; name=email^M
Content-Type: text/plain; charset=iso-8859-1^M
^M
foo@foo.com^M
--xnyLAaB03X^M
Content-Disposition: form-data; name=MAX_FILE_SIZE^M
Content-Type: text/plain; charset=iso-8859-1^M
^M
500000^M
--xnyLAaB03X--^M

Content-type: multipart/form-data; boundary=xnyLAaB03X
Content-length: 6981

--xnyLAaB03X
Content-Disposition: form-data; name=currfile; filename="/home/kiko/bookmarks.html"

PCFET0NUWVBFIE5FVFNDQVBFLUJvb2ttYXJrLWZpbGUtMT4KPCEtLSBUaGlz
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