oracle Installation help required

I am installing oracle 10g on RHL 5 . with Ignore prerequisits clause .
But whenever i says runInstaller it runs some part and gives me following message

Error in writing to directory /tmp/OraInstall2009-05-31_03-19-30PM. Please ensure that this directory is writable and has atleast 60 MB of disk space. Installation cannot continue.

my system configuaration as follows

OS : RHL 5.0
RAM : 512 MB
P4

an early help is appriciated .

It looks like you're running out of disk space.

tmp should be world writeable, you are probably low on disk space, what is output of

Code:

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df -h
ls -l / | grep tmp

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