Mozilla/Netscape 6+ does not calculate the rows and cols attributes
correctly. If you specify a TEXTAREA with rows=10 and cols=20, you will get a control
that is about 22 cols/characters wide by 11 rows/characters. It appears that the
difference is pretty constant - generally about 3 extra cols wide and one extra row tall.
The reader that pointed this out to me also noted it appears that Mozilla is allowing
space for the scroll bars in addition to the rows/cols you specify, even though they
are not present by default. (bugzilla #33654.)