Unicode and PDF tooltips / messageboxes with iTextSharp - unicode

Question

I need to find a way to add a quite long string in a quite small space in a PDF document.
I am using iTextSharp. I have already tried adding comment annotations (balloons) with PdfAnnotation.CreateText() and I didn't like the way they looked/worked. It made the page too heavy (I had many comments per page) and their behavior was odd in many ways (thank Adobe for that).
Now I was thinking of adding some simple tooltips on 'chunks' in the page or popping-up messageboxes with javascript (like illustrated here : http://www.codehacker.com/ITEXTSHARP/chap15.aspx#). To my great disappointment however, it seems that Acrobat (?) doesn't support Unicode characters in those situations. E.g. I do this:
var javascript = new PdfAnnotation(
w, 200f, 550f, 300f, 650f,
PdfAction.JavaScript("app.alert('" + "Αρνάκι άσπρο και παχύ!" + "');\r", w));
chunk.SetAnnotation(javascript);
...and, in the best case, a messagebox with gibberish pops up when the user clicks on the chunk.
Is there any setting for making Unicode acceptable for the code above or another way to do what I want?
EDIT:
I have now seen this: https://stackoverflow.com/a/163065/964053
and I've tried modifying my code like that:
var javascript = new PdfAnnotation(
w, 200f, 550f, 300f, 650f,
PdfAction.JavaScript((char)0xFEFF + "app.alert('" + "Αρνάκι άσπρο και παχύ!" + "');\r", w));
chunk.SetAnnotation(javascript);
But nothing seems to change...
EDIT2 :
Using octal representation e.g. (\141) doesn't seem to help either...
EDIT3 :
This seems to work nice until you double clink on it, but I need to make the tooltip size itself based on the contents size:
var lToolTip = PdfFormField.CreatePopup(
w, new Rectangle(tc.Left, tc.Bottom, tc.Right, tc.Top), val, true);
chunk.SetAnnotation(lToolTip);
The rectangle provided doesn't seem to be used in any way...
Any ideas?
I don't know what PdfFormField.CreatePopup() is supposed to create, but I see a small mark on my page that displays a popup when you hover the mouse over it.

Answer 1

I'm kind of lost in your edits, it's not clear what works for you and what doesn't, but regarding the unicode problem in JavaScript: are you aware that there are two versions of the javaScript() method?
See javaScript(java.lang.String, com.itextpdf.text.pdf.PdfWriter, boolean)
If you add the boolean value true, the JavaScript string should be interpreted as Unicode. If this doesn't solve your problem, I'll delete this answer, and if you clarify your question (cutting away the irrelevant parts), I'll do another attempt.