[Groff] tbl for html?

[Bill Ward]

Hello,

The html feature of groff does a great job for me with respect to turning
equations and tables into images for display on web pages.  Unfortunately,
my webmaster has pointed out to me that the "Americans with Disabilities
Act" suggests (mandates) that web pages be text where possible so that
various text to voice programs can translate web pages for blind users.
Tables formatted as images defeat these programs.

Three questions:

1. Does anyone have a satisfactory version of tbl that will work with groff
and produce html tables?

2. Failing 1, if I wrote my own (limited in scope) tool to do this, how can
I convince groff to call my tool when -Thtml is specified instead of regular
tbl, preferably without explicitly writing out the entire tool pipeline
myself (yuck).  

3. More generally, is there a way for me to create my own troff preprocessor
program and specify some option to groff so that groff will call my filter
program?

Any other more innovative solutions or suggestions would be well received.
Thanks in advance and

Best regards,

Bill Ward
ERDC MSRC
Vicksburg, Mississippi