Internal Server Error when updating a Network Activated plugin

Hi,

By mistake I've just tried to update a network acitvated plugin (with Pretty Plugins).

I set a Image URL then clicked on the "Update" button.
After about 30 secondes I got an Internal Server Error message.
I don't know if it's related to the fact it is a network activated plugin or if it's just a coincidence.
As a result my website was unavailable for a few minutes (it's back online now).

Here is what I see in my logs:
[Wed Mar 04 17:09:09 2015] [warn] [client xxx] mod_fcgid: read data timeout in 61 seconds, referer: http://xxx/wp-admin/network/plugins.php
[Wed Mar 04 17:09:09 2015] [error] [client xxx] Premature end of script headers: admin-ajax.php, referer: http://xxx/wp-admin/network/plugins.php
[Wed Mar 04 17:09:09 2015] [warn] [client xxx] mod_fcgid: read data timeout in 61 seconds, referer: http://xxx/wp-admin/network/plugins.php
[Wed Mar 04 17:09:09 2015] [error] [client xxx] Premature end of script headers: admin-ajax.php, referer: http://xxx/wp-admin/network/plugins.php
[Wed Mar 04 17:09:24 2015] [warn] [client xxx] mod_fcgid: read data timeout in 61 seconds, referer: http://xxx/wp-admin/network/plugins.php
[Wed Mar 04 17:09:24 2015] [error] [client xxx] Premature end of script headers: plugins.php, referer: http://xxx/wp-admin/network/plugins.php
[Wed Mar 04 17:09:49 2015] [warn] [client xxx] mod_fcgid: read data timeout in 61 seconds, referer: http://xxx/wp-admin/network/plugins.php
[Wed Mar 04 17:09:49 2015] [error] [client xxx] Premature end of script headers: index.php, referer: http://xxx/wp-admin/network/plugins.php
[Wed Mar 04 17:10:01 2015] [warn] [client xxx] mod_fcgid: read data timeout in 61 seconds
[Wed Mar 04 17:10:01 2015] [error] [client xxx] Premature end of script headers: index.php
[Wed Mar 04 17:10:12 2015] [warn] [client xxx] mod_fcgid: read data timeout in 61 seconds, referer: http://xxx/wp-admin/network/plugins.php
[Wed Mar 04 17:10:12 2015] [error] [client xxx] Premature end of script headers: admin-ajax.php, referer: http://xxx/wp-admin/network/plugins.php
[Wed Mar 04 17:10:13 2015] [warn] [client xxx] mod_fcgid: read data timeout in 61 seconds
[Wed Mar 04 17:10:13 2015] [error] [client xxx] Premature end of script headers: index.php
[Wed Mar 04 17:10:59 2015] [warn] [client xxx] mod_fcgid: read data timeout in 61 seconds
[Wed Mar 04 17:10:59 2015] [error] [client xxx Premature end of script headers: index.php
[Wed Mar 04 17:11:37 2015] [warn] [client xxx] mod_fcgid: read data timeout in 61 seconds
[Wed Mar 04 17:11:37 2015] [error] [client xxx] Premature end of script headers: index.php

Any idea of what happened?

Best Regards