Java plugin JVM parameters

we are using Debian Squeeze with iceweasel and sun java6

java-common        0.40          Base of all Java packages
sun-java6-bin      6.22-1        Sun Java(TM) Runtime Environment (JRE) 6
sun-java6-jre      6.22-1        Sun Java(TM) Runtime Environment (JRE) 6
sun-java6-plugin   6.22-1        The Java(TM) Plug-in, Java SE 6
iceweasel          3.5.15-1      Web browser based on Firefox

we need to limit the amount of memory java uses when an applet is loaded from the web. By default we see it is using arround 400MB which is a very high value since it is running in kiosk terminals with 512-1024MB of RAM.

in the folder of the user running iceweasel there is a .java/deployment folder with a deployment.properties file:

#deployment.properties
#Fri Feb 11 08:07:23 UTC 2011
deployment.version=6.0
deployment.capture.mime.types=true
deployment.browser.path=/usr/bin/firefox
#Java Deployment jre's
#Fri Feb 11 08:07:23 UTC 2011
deployment.javaws.jre.0.registered=true
deployment.javaws.jre.0.platform=1.6
deployment.javaws.jre.开发者_高级运维0.osname=Linux
deployment.javaws.jre.0.path=/usr/lib/jvm/java-6-sun-1.6.0.22/jre/bin/java
deployment.javaws.jre.0.product=1.6.0_22
deployment.javaws.jre.0.osarch=i386
deployment.javaws.jre.0.location=http\://java.sun.com/products/autodl/j2se
deployment.javaws.jre.0.enabled=true
deployment.javaws.jre.0.args=

This file is created if down't exists when an applet is run. I set deployment.javaws.jre.0.args=-Xmx128m but don't seem to follow it

I had been tweaking with the parameters and some of them seem to be honored -Xms and -Xmn but not sure which is the parameter I must set to limit the total amount of memory java can use. I always get:

PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND  
3007 user      20   0  **379m**  34m 8184 S  0.7  3.6   0:04.84 java

Regards

As far as I can recall the only way to set the Xmx for java plugin is via the java control panel. It has got default value there that overrides the other settings.