Cannot compile scilab

I had a difficulty with scilab, it would not plot! an would give me error 21. and crash.!
I could not figure it out.
I tried to install from source. and this is where real trouble came
./configure crashed with the following error

checking Symlink for /usr/lib/jvm/java-1.5.0-gcj/bin/javac… Filename changed… Keeping the one found before
Java base directory (probably) available here : /usr/lib/jvm/java-1.5.0-gcj
checking for zip or jar files to include on CLASSPATH…
checking to see if the java compiler works… configure: error: Could not compile simple Java program with ‘/usr/lib/jvm/java-1.5.0-gcj/bin/javac’. Try with the Sun JDK (1.5 or 6).

I changed to the directory to find this

alon@linux-6xrt:~/Downloads> cd /usr/lib/jvm/java-1.5.0-gcj/bin/
alon@linux-6xrt:/usr/lib/jvm/java-1.5.0-gcj/bin> ls
appletviewer jarsigner javac javah rmic
jar java javadoc keytool rmiregistry

It seems that the java compiler does not work?
I installed javacc…
No avail, any ideas?
how to make ./configure work? Is there a java compiler somewhere else I could use?


In addition I wish to add the error codes I got from my scilab 5.1.1 session initially

Startup execution:
loading initial environment


Warning !!!
Scilab has found a critical error (Unknow exception).
Save your data and restart Scilab.
!–error 21
Invalid index.

at line 157 of function plot called by :

hi everyone can anyone solve my prob.
this is my question i have a excel file with date, time and no of hits, i have extracted these from excel file into a .dat file using scilab, now i need to find sum of hits for a day(hits is calculated for every 30 mins for a day so there will be 48 hits for a day) this is my code

can anyone suggest a solution for this(can come with a peice of code to this work)

thank you