Line wrapping with proportional fonts

[Dave Abrahams <dave@xxxxxxxxxxxx>]

This bug report will be sent to the emacs-w3m development team,
 not to your local site managers!!
Please write in simple English, because the emacs-w3m developers
aren't good at English reading. ;-)

Please describe as succinctly as possible:
	- What happened.
	- What you thought should have happened.
	- Precisely what you were doing at the time.

Please also include any Lisp back-traces that you may have.
================================================================
Dear Bug Team!

When I invoke `M-x variable-pitch-mode' in a w3m buffer, lines commonly
extend beyond the right side of the window before they wrap.  In case
this is impossible to address correctly and completely due to line wraps
being calculated on the basis of a fixed character width, it would help
if we could specify a margin width to be subtracted from the physical
width when calculating line wraps.

================================================================

System Info to help track down your bug:
---------------------------------------
emacs-w3m-version
 => "1.4.446"
emacs-version
 => "GNU Emacs 24.0.94.1 (x86_64-apple-darwin11.3.0, Carbon Version 1.6.0 AppKit 1138.32)\n of 2012-03-14 on pluto.luannocracy.com"
mule-version
 => "6.0 (HANACHIRUSATO)"
system-type
 => darwin
(featurep 'gtk)
 => nil
w3m-version
 => "w3m/0.5.3"
w3m-type
 => w3m-m17n
w3m-compile-options
 => ("lang=en" "m17n" "color" "ansi-color" "mouse" "menu" "cookie" "ssl" "ssl-verify" "external-uri-loader" "w3mmailer" "nntp" "ipv6" "alarm" "mark")
w3m-language
 => nil
w3m-command-arguments
 => nil
w3m-command-arguments-alist
 => nil
w3m-command-environment
 => nil
w3m-input-coding-system
 => utf-8
w3m-output-coding-system
 => utf-8
w3m-use-mule-ucs
 => nil

-- 
Dave Abrahams
BoostPro Computing
http://www.boostpro.com