Quote - > Quote - Hm, what about a Gaussian function applied ot it? :)

Good question. Maybe ArtPearl can help...

No help from me I'm afraid. Well, not positive help.
nruddock is absolutely right - there is an inherent deficiency with the fe nodes - they only operate on one point of the map at a time. For any sort of blurring you need to know what the values of the neighboring points so you can average them.  So you cant simply use one node.
It shouldnt be hard to set up something similar to his suggestion - having 4 (or 8) copies of the map each shifted slightly in the u/v directions and add/average them up.
But I dont think that will help the OP.
First, there is a problem at the edges, because there are no  neighboring points, at least on one side, to average. That may or may nor be important depending how much the texture map covers and how close it is to the edge.
What is worse is the area of seams. The suggested method will add and average the wrong values. Next to a seam point there will be points with no meaningful value (possibly white) and adding them  will screw up the blurring. Instead of averaging those points, one should add the corresponding point on the other side of the seam. These will not be right next to each other on the map.
You could easily try this out in a 2d editing program - just make 4 layers with shifted maps and merge them. I think you'll get the same (or similar) unsatisfactory results as you got by using the blur function directly - screwed up seams.
The only way around it that I can think of is to get duplicate regions near seams. Then you can apply the blurring in the 2d application or in vue the way nruddock suggested. The practicality  of this depends on the complexity of  the specific case.
Are you sure there isnt something in 3dcoat that could do it? (never used it myself) because that is the only stage that 'knows' what's on both sides of the seam.
Sorry I dont have a practical/quick solution, maybe someone smarter & more knowledgeable will.

Good luck

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