Font 'Arial' is not available to the JVM. See the 

 

I have resolved this like this:

first get the microsoft core fonts. In Ubuntu 12.04 this package is called:

 ttf-mscorefonts-installer

# su root
 password :

Download msttcore fonts rpm to install

1. wget http://www.my-guides.net/en/images/stories/fedora12/msttcore-fonts-2.0-3.noarch.rpm

Install the downloaded  rpm by below command

2. rpm -Uvh msttcore-fonts-2.0-3.noarch.rpm

After install you can see the fonts in: /usr/share/fonts/msttcore

#mkdir  /usr/lib/jvm/java-1.7.0-openjdk-1.7.0.45.x86_64/jre/lib/fonts

copy all the ttf files to your JAVA_HOME/jre/lib/fonts

general JAVA_HOME should be /usr/lib/jvm/java-1.7.0-openjdk-1.7.0.45.x86_64

I had to do a restart of iReport to be resolved of the error.