gawk 3.1.3 case insensitive bug?

Hi,

I am switching from gawk 3.0.6 to 3.1.3 and found that case sensitivity is l
ost:


399> gawk --v
GNU Awk 3.0.6
...snip...
400> echo "A" | gawk '{if ($0 ~ /[a-z]/) print "INSIDE"}'
401>


340> gawk --v
GNU Awk 3.1.3
...snip...
341> echo "A" | gawk '{if ($0 ~ /[a-z]/) print "INSIDE"}'
INSIDE
342>

Has anybody experienced this?  I have not seen any explanation on the web,
on-line manuals, or newsgroups.  Setting IGNORECASE to zero does not help.

Thanks for the help,

Mark