Weird problem with invalid image

Error 20081103070909 NOTICE: db/class_file.inc.php : 687 Undefined variable: new_width
Error 20081103070909            pages/file.inc.php : 717 -> File::viewAsImage("100")
Error 20081103070909 std/class_pagehandler.inc.php : 729 -> fileDownloadAsImage()
Error 20081103070909                     index.php : 210 -> PageHandler::show("fileDownloadAsImage")
Error 20081103070909 
Error 20081103070909      Variables in fileDownloadAsImage():
Error 20081103070909                      max_size = 100
Error 20081103070909                    dimensions = Array
Error 20081103070909                         image = NULL
Error 20081103070909    v0.0808, fileDownloadAsImage, from 202.53.13.107,  uri:/index.php?go=fileDownloadAsImage&file=3416&max_size=100
Error 20081103070909 
Error 20081103070909 NOTICE: db/class_file.inc.php : 687 Undefined variable: new_height
Error 20081103070909            pages/file.inc.php : 717 -> File::viewAsImage("100")
Error 20081103070909 std/class_pagehandler.inc.php : 729 -> fileDownloadAsImage()
Error 20081103070909                     index.php : 210 -> PageHandler::show("fileDownloadAsImage")
Error 20081103070909 
Error 20081103070909      Variables in fileDownloadAsImage():
Error 20081103070909                      max_size = 100
Error 20081103070909                    dimensions = Array
Error 20081103070909                         image = NULL
Error 20081103070909    v0.0808, fileDownloadAsImage, from 202.53.13.107,  uri:/index.php?go=fileDownloadAsImage&file=3416&max_size=100
Error 20081103070909 
Error 20081103070909 WARNING: db/class_file.inc.php : 687 imagecreatetruecolor() [<a href='function.imagecreatetruecolor'>function.imagecreatetruecolor</a>]: Invalid image dimensions
Error 20081103070909         db/class_file.inc.php : 687 -> imagecreatetruecolor(int0, int0)
Error 20081103070909            pages/file.inc.php : 717 -> File::viewAsImage("100")
Error 20081103070909 std/class_pagehandler.inc.php : 729 -> fileDownloadAsImage()
Error 20081103070909                     index.php : 210 -> PageHandler::show("fileDownloadAsImage")
Error 20081103070909 
Error 20081103070909      Variables in viewAsImage():
Error 20081103070909                      max_size = 100
Error 20081103070909                    dimensions = Array
Error 20081103070909                         image = NULL
Error 20081103070909    v0.0808, fileDownloadAsImage, from 202.53.13.107,  uri:/index.php?go=fileDownloadAsImage&file=3416&max_size=100
Error 20081103070909 
Log 20081103070909 guest@202.53.13.107 -> fileDownloadAsImage /index.php?go=fileDownloadAsImage&amp;file=3417&amp;max_size=100  (Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.0.1) Gecko/2008072820 Firefox/3.0.1)