The first step is to copy the already installed java apps to the Memory card.
First create two directories named "asd" and "java" in the root of the the memory card.
Then copy this script into startup.txt in tools folder to copy the contents from phone memory to Mem card
#!/bin/sh
cd /mnt/fat/
cp -R /mnt/jffs2/app_data/java .
Since this is a startup script. Restart the phone.
Now we have to bind the java folder in the phone memory to the java folder in the mem card
For that copy the following script into the startup.txt in tools folder again
#!/bin/bash
mount -o bind /mnt/fat/asd /usr/share/usr_data/asd
mount -o bind /mnt/fat/java /usr/share/app_data/java
Restart the phone once more you're done. All the apps will be installed to the mem card instead of phone memory
If you're too lazy to type the scripts you can download the scripts from the link below
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Enjoy!!!!