404 error for new blog posts on e-mail

Hi

I've just noticed an issue with our blog component (despite using it for some time!). The issue is simply that when we issue a new blog post these get distributed to the subscriber list via e-mail. However the links that are provided in the HTML e-mail result in a 404 error. For example, we released a new post yesterday which has the following URL from the front-end:

http://www.stickerscape.co.uk/entry/our-in-the-night-garden-wall-sticker-range-is-now-available

However the link in the e-mail is the following which results in a 404 error:

http://www.stickerscape.co.uk/blog/entry/our-in-the-night-garden-wall-sticker-range-is-now-available

Is anyone able to advise what's causing this? I've had a look in the settings to see if I can amend the SEF URL that's created but can't see anything. We use AceSEF component across the rest of the site for creating SEF URLs so I'm not sure if that's causing a conflict?

Anyway any thoughts would be much appreciated.

Regards

Mike