Crystal Reports Problems with Unicode and ExportToDisk to PDF

Message

   I have a small program which prints a document, which contains Chinese 
and Arabic symbols and then saves it as PDF. Printing works perfect, but
 the generated PDF doesn't display the Chinese characters correctly.

Here is the sample pseudo code of my program

	Code:
	CrystalDecisions.CrystalReports.Engine.ReportDocument reportDocument = new ...;
...
reportDocument.PrintToPrinter(printersettings, pagesettings, false); // this works perfect. E.g. I have the Chinese printed via physical printer.
reportDocument.ExportToDisk(ExportFormatType.PortableDocFormat, m_FileName); // Here when open the pdf I see a squares instead of Chinese symbols.
I tried to change the font in rpt to "Arial Unicode MS" or "Lucida
 Sans" or to many other fonts, which should support Unicode but no 
effect. I can see the Araby letters, but cannot see the Chinese.

If I change the font to "MingLiU", the Chinese symbols are displayed OK in the PDF, but then I can't see the Arabic letters 

Thanks in advance,

Kalin