Just a note: I don't think I've ever heard the phrase "fun to be around with", it just doesn't sound right. "Fun to be around" or "fun to be with" are both fine, but not together.

@Nicole: It is popular expecially in the Midwestern and Western States where I have heard it numerous times.

Google hits for

"fun to be around with": 19.100
"fun to be around": 983.000
"fun to be with": 411.000
"a fun person to be around": 19.200

I can't quite reproduce your google results, Carola. Have you searched for "fun to be around with" (in quotation marks) or just fun to be around with? I could only come up with 787 hits for "....around with" (quite a few of them of the "I'm looking for someone who is fun to be around [,] with a good sense of humour and..." variety) compared to 421,000 for "fun to be around" - which clearly supports Nicole's point.
Like Nicole, I don't think I've ever heard the expression "...around with" but then, I'm not from the Midwest.
To be honest, the proposed German entry "Mit ihm macht's Spass" doesn't sound quite right either. If someone used this expression, I'd wonder: "was macht Spass mit ihm - Sex, Drogen, Rock'n'Roll?". The second suggestion "Er/sie ist total nett" sounds much more natural.

@bike_helmut: Thank you! You are right, there are only 787 hits for "fun to be around with", I really don't know how I got the 19.100.

But even if you eliminate the "fun to be around, with" you still end up with approximately 650 hits, proving that the expression is used.

I don't insist, though, and I would be happy if at least "fun to be around" and "a fun person to be around" made it into LEO... ;-)

It must be a distinctly midwestern thing - I've never heard it here in Michigan, nor in Tennessee when I lived there when I was younger. I still think as a dictionary entry though it might be safer to say around or with or at least label "around with" as being a regional kind of thing...just to avoid confusion to those in areas that don't use that.

>>even if you eliminate the "fun to be around, with" you still end up with approximately 650 hits

Um, how? Did you read each one of the 787 occurrences yourself and tally them as to comma, implied comma, or no comma? Because as far as I know, Google deliberately ignores all punctuation, so there's no way to do it automatically -- or if there is, perhaps in a better search engine (my constant dream), I'd like to know about it.

I agree that 'fun to be around' and 'fun to be with' are fairly common, but I'm not sure that 'fun' is unique in this kind of construction. People can be exciting to be around, depressing to be with, interesting to observe, amusing to hang out with, annoying to have to put up with, and so on more or less ad infinitum.

Also, it would be better to formulate it in neutral, inclusive language, rather than as an example with 'he.'

If it were going to be added, it might still be good to if German speakers could suggest a better translation.

'Mit jdm. macht's Spaß' seems closer in sense, but do others agree with bike_helmut that it's not very idiomatic?

'Total nett' is more idiomatic, but it doesn't really mean the same thing. Someone who likes wild parties or sarcastic jokes could be fun to be around (for someone else who shared that taste) without necessarily being at all a nice person.