How to get rid of "The form cannot be displayed because session state is not available"

I know other people wrote about this in the newsgroups, but strangely enough - no blogger bothered to blog about this - so I will.

When you click on "start workflow" in a publishing site page, you get the annoying error "The form cannot be displayed because session state is not available". This will happen even if the "Configure Session State" in the "Application" section in the administration site is configured properly.
The solution is simple - open the web.config file for the site, search for the word "SessionStateModule" and uncomment that line.

Example:
<!-- <add name="Session" type="System.Web.SessionState.SessionStateModule"/> -->
should be:
<add name="Session" type="System.Web.SessionState.SessionStateModule"/>>

Notes about Workflow

Lately I had to write some workflows in visual studio for the first time. I loved the interface, and the richness of options. I cant wait until I get to work with either K2 or Captaris and see how they enrich my workflow environment, but for now the built in workflow action that come with .net3 seem very cool.

I did have some problems though. On my development machine the "delay activity" wouldn't finish.
The delay activity is a cool way to tell the workflow to stop and wait for a specific time. We used it for task reminder setting - the workflow was supposed to wait until the task was due, and then send an email to the task owners. The way to do it is simple - in the delay activity "initializeTimeOutDuration" event you check the task list item "due date" field, and then calculate the time from that date to the "now" date, and set the "TimeoutDuration" property of the activity to that timespan.
The problem was- it didn't work!
After much research I got another machine going, and deployed the workflow there. works like a charm. I noticed that on my dev machine sharepoint is out of synch with the system clock. while the system clock said it was 10am, sharepoint was claiming it was 11am. I guess that messed up the workflow timer. I still don't know how to fix this.

Another interesting thing - The delay activity seems to operate in 10 minutes time units. There is no point in setting a delay activity to 1 second as opposed to 2 seconds or 10 seconds. both will fire at the next timer event which seems to occur once every so often (10 minutes? who knows?). So don't count on the engine for realtime applications (-:

The last thing I wanted to note was that the sharepoint "logToHistoryListActivity" is a great function to use to debug your workflow without going into code, not to mention it can be used to let users know the status of the workflow and what was done. But beware - appearntly each once of these activities can only store a limited amount of characters (my guess is 256, but I didn't check). So limit your logging to a minimum, and don't expect a stack trace to be properly logged there.