ramon fincken

Auto sets the more tag to post title if no custom text has been set. 
 Auto text is customizable using mp_auto_more_more_link_readmore filter in the Premium version: 
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MP Auto more tag

Auto sets the more tag to post title if no custom text has been set.

mountbatt

This plugin adds a separator between the intro text and the extended (more…) text of the content of a post. It simply replaces the span id more tag with the separator that is set in the plugins php file.
Some separator samples are given there.
Upload into the /plugins directory and activate it in the Plugins Menu.
History:
1.1:
Fixed a bug that forced WordPress Adminmenu to show a white blank page.
1.0:
Initial Release

Add a Separator

Simple Plugin to add a separator between the intro and the (more...) content.

MP Auto more tag vs Add a Separator