[PHP-INSTALL] code php return a white page

[Ana Diez]

Hi to all.
I have got a solaris 9 with Apache 1.3.27 + PHP 4.3.2 (libphp4.so).
At the begin all work ok but sometimes, when I access to a php page
(info.php), it shows a white page.
And no errors in the logs.
What's happens? Somebody have this problem?
Thanks!
Ana B. Díez