WSOD occurs when using Embedded Media Field 5.x-1.3 in Drupal 5.14

emfield 5.x-1.x-dev and 5.x-1.2
Drupal 5.10
MySQL 5.0.37
PHP 5.2.6
Apache/1.3.34

We have problems with WSODs - and could it just solve by disabling emfield.
We have an own content type which has a field (contemplate) for videos.

When adding or editing a node sometimes it comes back with a WSOD, while most of the time the node is saved, sometimes without taxonomy tags or without a path from pathauto.

It is very hard to debug, because it doesnt come up everytime you save a node...

Anyways, the error is a classic Out of memory WSOD:
PHP Fatal error: Out of memory (allocated 73400320) (tried to allocate 6 bytes) in /home/www/doc/11111/host.com/drupal/includes/database.mysql.inc on line xxx

No matter how high we set the allowed memory (it's at 128M now, was at 265M without any changes), it will always come up with that error.
I know all other hints about WSOD (utf-8, no BOM, closing php tags, etc.) - I tried everything, no solution.

Do you have any idea what this could be? Thank you!