Drag the link below into your link toolbar! Right click on your toolbar to display the link toolbar if it is not visible. If you can't drag this link (Windows sp2), right click on the link and add it to your favorites. Specify the "Links" directory and it will show up on your toolbar.
When you are editing an MSN Spaces a blog entry, click on this toolbar button to display a few additional commands and enable an HTML editing mode. Note that MSN Spaces does not allow quite a bit of HTML so there are no promises that the formatting will be preserved when you publish your entry.
For more information, see my blog.