Hello guys! I'm having this terrible problem also and I made some research. Here's what my progress so far:
1. I am using Isis Template (For Administrator), and Beez Template (For Site).
2. I uses the debug tool of Google Chrome (Press F12 on your google chrome web browser to launch it)
3. Open both admin and site pages in different tabs
4. Examine the list of .css file loaded on separate tabs
When I look closely, I am not seeing a "template.css" on the site page, but in the admin page I can see. When you hover the mouse to the field that launches the tooltip, there's a "div" tag inserting below the "label" tag and it has a class name "tooltip fade top in". I searched for the entire .css files of the Beez template but I cannot see it.THAT IS WHAT IS MISSING! [As I thought ]
What you have to do is open the "template.css" of the Isis template using Notepad, copy the entire "tooltip" class starting from ".tooltip" up to ".tooltip.bottom .tooltip-arrow" (lines 3958 to 4033), and paste it to the one of the .css file where Beez template is using. I tried "personal.css" and paste the entire code class at the bottom.
Save it (don't close yet), go back to google chrome and activate the site tab, hit refresh (F5) and check if there's any changes on the tooltip.
The tooltip shows but it is not in the right position. I haven't tweaked the codes yet. Maybe if you find a fix please post it here. I'll try it tomorrow.