Trouble in 'javac' in EL4

[mamoon]

hi all,
background information:
1. OS- RedHat Enterprise Linux4
2. JDK installed- java-1.4.2-gcj

hi, i am a newbie trying to compile my java programs. i checked whether any JDK is installed on my system (RHEL4) with following command as a root:

/usr/sbin/alternatives --config javac

it replies:

There are 1 programs which provide 'javac'.
 
  Selection    Command
-----------------------------------------------
*+ 1           /usr/lib/jvm/java-1.4.2-gcj/bin/javac
 
Enter to keep the current selection[+], or type selection number:

i entered to keep the current selection. i have my java progms in my home directory. when i tried to compile progm as follows:

/usr/lib/jvm/java-1.4.2-gcj/bin/javac HelloWorldApp.java

it gives error:

Aborted

can anyone help what problem i am facing? it is urgent.
with regard
mamoon