Allow references to be placed on a diagram (in the same way you can add a loop to the diagram) with the word ref in the top left and a guard statement.

If I need to create a multiple diagram then I would like to add header to each diagram. Having header will be a valuable to me. something like, head: Success Path for JMS Message

Normally these Sequence Diagrams will be inserted in a Document. so if a feature like creating the diagram in multiple picture images it will be much helpful,,

Try tool like reversejava to get the idea. Very useful for understanding a new tool.

New website looks great, thanks. Please migrate all the old features to this new site, including zooming capability (very important). Please find another spot were to place the diagram type drop-down box, it overwrites the diagram content. Other than that great work.

The spacing of classes is currently driven by the length of the function call strings.

I couldn't use your (wonderful!) service, because I needed to have compact diagrams.

Rose does allow you to control spacing of the text boxes, and the text of functions just "overflows" the arrows from both sides.

I suggest an addition to your 'participant' command, add a 'space' parameter to it.

Sequence diagrams are généraly associated with FSM diagrams. The ability to produce FSM would be nice

I would love to have a similar tool that produces the "memory box" style of diagrams often used to document packet or struct layouts.

I seriously believe this option is so crucial. It doesn't make sense that packets (or whatever) get sent in zero seconds.. most sequence diagrams must show some sort of delay. Please add a feature to provide users the option to input their required angle.
Thanks

If you have not already then you should start open source plugin projects for integrating with netbeans & eclipse and also increasing the uml functionality coverage of this very user friendly tool

A y-axis that shows time and perhaps some horizontal support lines per timeunit. And the option to set duration of actions. Ex: activate: End-of-day duration: 1h30m

For large diagrams, the ability to repeat the participants part way down would greatly help

I would like to have the possiblity to make a animated presentation in powerpoint. have tried wmf conversion of a eps file but this does not work well.

Actions in a sequence diagrams may also be started by actors who are ideally represented on the left most side of the sequence diagram you can use [ ] to represent actors like

[Bob]->PizzaRequestForm:Submits
[Bob]->PizzaCancelForm:Submits

the resultant diagram should have figures of actor named Bob on the left with an arrow for Submits to the PizzaRequestForm & PizzaCancelForm respectively one below the other

Have diagram text entered in a different window than the diagram picture. Most of the time I scroll between picture and text without being able to have a full view of any of them. You could use a pop-up window just for diagram and allow a bigger size for text window ... or any other ideea to separate text from picture while allowing a better user experience. Anyway, great tool, Thanks !!!

Support embedded hyperlinks so we can hide/show details on demand.