I'm using calibre on more than one computer and everytime I'm importing some ebooks from one computer on the other the tags get messed up!
For example:
Tags for an ebook on computer 1 are:
Science Fiction, Perry Rhodan
If I import this ebook on computer 2, the two tags are combined forming the following tag:
Science Fiction; Perry Rhodan
This is sort of stupid and I've to correct the tags manually!