Random problem with theme encoding on browser refresh

Hi!

We are having a really strange problem. Looks very random. Page has custom template defined. This template has some special UTF-8 characters included in text (like Več for More). Now – sometimes this pages gets rendered just fine and sometimes after refresh in browser this special characters are shown as ? (like Ve?).

We have checked encodings and UTF-8 is used everywhere.

You can try refreshing this URL in your browser:
http://www.zac.si/arhiv/arhiv-iz-hise-pisanih-spominov/

Sooner or later you will notice ? instead of some characters in the title (hiše will change to hi?e). This title is hard coded in template file.

What could be the problem?

Tomaz