Problems with chart creation on Ubutnu

I have not seen this error before, but when I try and create a chart I
get this error http://pastebin.com/ZDKDqBWK.
If I set the this environment variable

export JAVA_OPTS="-Djava.awt.headless=true"

I am able to generate charts.

Not sure if this has been documented before or not (I probably have
sent a similar email to the list, I did not check the archives=
.

Seems not to be a problem necessarily with DHIS2, but maybe with the
system configuration.
I am using Ubuntu Ibex, Java 1.6.0_19, Tomcat 6.0.24 and the latest
version of the code on a local installation.

Regards,
Jason

ยทยทยท

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Jason P. Pickering
email: jason.p.pickering@gmail.com
tel:+260968395190