Edit WordPress Plugin to clear chat messages every x hours instead of every day

Avg Bid (USD)
Project Budget (USD)
$30 - $250

Project Description:
We are testing two chat plugins on our site to see which is best. However, of the two we have selected, neither provides all the options that we need.

The options we need are:

1) Clear messages every x minutes
2) Leave x messages active (latest messages) when clearing older messages
So, if we set it to clear messages every 60 minutes and leave 30 messages, it should clear all messages from the database (assuming they are stored within the database) every 60 minutes, leaving the latest 30 messages. It must do so in the best possible method to ensure that the database is not overloaded during the clearing process. Maybe the removal could be done in batches using either the wordpress cron system or using a manually setup cron on our server. You should also ensure that the language files are not corrupted by the changes you make and the new items you add have appropriate entries within the language files.

The two plugins and their current options are listed below:
1) Quick Chat
Download: http://wordpress.org/support/plugin/quick-chat
The plugin has also been attached to this project listing.
We need to be able to remove messages every hour, leaving the last x messages. I would really like control over this so that we can tweak the settings to get the best results. Please create an entry box within the plugin settings where we can add a value in minutes to set the frequency of the chat messages being cleared.

2) Schreikasten
Download: http://wordpress.org/extend/plugins/schreikasten/
The plugin has also been attached to this project listing.
Schreikasten has a lot more, better options. It allows us to set the frequency of clearing messages as a fraction of a day. Ideally, I would like this to be converted into minutes so that we can enter more accurate timing and I would like it to be set so that we can leave x messages.

Skills required:
PHP, Software Architecture, Wordpress
Additional Files: quick-chat.zip
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