Steps to Reproduce:

1. Create a label with non-ASCII characters (i.e. てすと) and attach it to more than 10 pages
2. Click on the label and attempt to go to browse to page 2
   Note the error text:

   The following error(s) occurred:
   
       Please specify a label id.
   

Thoughts
If you look at the URL on the first page of the list of pages with that label, you'll see something like this:

http://localhost:10513/confluence/labels/viewlabel.action?ids=2457603

If you go to the second page, you'll see this in the URL:

http://localhost:10513/confluence/labels/viewlabel.action?startIndex=10

What it should look like (and this is the way you can work around this problem) is:

http://localhost:10513/confluence/labels/viewlabel.action?ids=2457603&startIndex=10