icons in proprietary software that resemble free icons?

[Ben Pfaff]

[I sent a copy of this to address@hidden a month or more ago,
and did not ever receive a response, so I am trying address@hidden
now.]

GNU PSPP has a "toolbar" with a row of icons that invoke various
functions.  PSPP is a clone of the functionality of the
proprietary software program SPSS, which also has a toolbar.
Some of the toolbar icons in PSPP resemble those in SPSS that
perform similar functions.  The PSPP icons are not
pixel-for-pixel copies; rather, they were drawn independently but
depict similar objects, actions, etc.

Screenshots of SPSS showing the icons in question are not
difficult to find on the web; e.g.:
        http://appdb.winehq.org/appimage.php?iId=2514
The corresponding PSPP icons are available via Savannah.  You can
click on any of the .png files at the URL below, then click on
"View" or "Download" to see the icon:
        http://cvs.savannah.gnu.org/viewcvs/pspp/src/ui/gui/icons/?root=pspp

Is this acceptable from a copyright point of view, or should we
design new icons for PSPP that do not resemble those used in
SPSS?

Thanks!

Ben

-- 
"Long noun chains don't automatically imply security."
--Bruce Schneier