[Plugin: Contact Form 7] Upload File = Validation Error

Is there a limit on the file size that can be uploaded via the ‘Upload File’. Or is there a time limit for uploading the file? My form works fine except for the file upload part. Even that works fine if the files are small. However as soon as you add a file that is more than 1mb or so, it throws out a validation error. Any ideas?

http://wowididit.com/submit/

http://ww.wp.xz.cn/extend/plugins/contact-form-7/