OpenSolaris Installer error

Hi,
Whenever i try to install OpenSolaris, I am getting the error
"There was an error launching the application.
Detail: Failed to fork child process (Not enough space)"

I am using the image 2009.06. I have 512 mb ram and 100 gb hard drive with Red Hat and Windows Xp installed. Please help.

512 MB RAM is not enough. At least 1 GB is required with 2 GB better.