captcha not working in ubuntu 10.10?

I recently changed to ubuntu OS and my captcha is no longer working. But it works fine in linux server... I am usin开发者_开发知识库g codeignitor.

Error in imagettfbbox function i am getting this error...

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Several things could go wrong. 1. Permissions for the img_path must be 777 or change the owner to www-data in order to gain write privs. 2. The font path for using the write font must be correct. 3. In order to use the captcha library you should have php gd extension installed. 4. And the last thing that could go wrong is the url path for the captcha image. Maybe the captcha is generated successfully but you are not accessing it correctly from the url.

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May be your php interpreter doesn't configured with php, also try to remove browser cache.

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I was facing the same problem. On shifting to ubuntu server captcha images stopped working. And changing the font path from 'monofont.ttf' to './monofont.ttf' worked for me. Just to be on the safe side, keep your font file and captcha script file in the same directory.