firefox memory leak

[L.V.Gandhi <lvgandhi@gmail.com>]

I am running sarge with backports using firefox. I found many times
system hanging. I am now only running firefox and konsole.
In the last 30 mins, free gives the following results at various
points of time sequentially as below. first one when I started
machine.
lvgandhi@lvgdell600m:~$ free
             total       used       free     shared    buffers     cached
Mem:        515736     315068     200668          0      14004     151484
-/+ buffers/cache:     149580     366156
Swap:       506008          0     506008
lvgandhi@lvgdell600m:~$ free
             total       used       free     shared    buffers     cached
Mem:        515736     509664       6072          0        648      53996
-/+ buffers/cache:     455020      60716
Swap:       506008      88732     417276
lvgandhi@lvgdell600m:~$ free
             total       used       free     shared    buffers     cached
Mem:        515736     509204       6532          0       2136      32340
-/+ buffers/cache:     474728      41008
Swap:       506008     264072     241936
After another 15 mins
lvgandhi@lvgdell600m:~$ free
             total       used       free     shared    buffers     cached
Mem:        515736     509720       6016          0       2932      38076
-/+ buffers/cache:     468712      47024
Swap:       506008     397072     108936

Any comments.
--
L.V.Gandhi
http://lvgandhi.tripod.com/
linux user No.205042