So, I had to create a PKCS#12 type or .p12 extension certificate from a java keystore which was created using java keytool. FYI, I have jdk 1.4.2. I came to know that using keytool you cannot export the private key.
I tried various options available in keytool i.e. create a keystore of type PKCS#12 to begin with instead of the default JKS (java keystore). -storetype PKCS12.
All this didnt work and on further search on google, I came across 2 free products which can help you a lot in terms of handling the keystore, generate keystore, export private key and so on.
You can download these free products from here.
The tools are portecle-1.5 http://sourceforge.net/projects/portecle/
KeyTool IUI – GUI http://www.icewalkers.com/download/KeyTool-IUI/3073/adl/
For my needs, i.e. generate a PKCS#12 certificate from an existing java keystore, portecle-1.5 worked just fine and it was very easy to use.
I also tried the KeyTool IUI – GUI just for testing the tool and it helped me to export the private key of my RSA key pair. The reason I wanted my private key in a seperate file is to use this online site which allows conversion of certificate types online. The url is https://www.sslshopper.com/ssl-converter.html.
Hope this helps someone. :-)
Helpful Links/Tutorial for keytool, PKCS#12 :
Cryptography Tutorials - Herong's Tutorial Notes
Keytool to OpenSSL Conversion tips
Exporting the Private Key from a JKS keystore
Exporting keystore private key with WSAS
Exporting Private Keys
Good Luck. :-)