In reference to your last comment, try the following code:
<cfset demo_pdf = CreateObject("java", "aspose.pdf.Pdf").init() >
<cfset section = CreateObject("java", "aspose.pdf.Section").init() >
<cfset sec1 = demo_pdf.getSections().add() >
<cfset text = CreateObject("java", "aspose.pdf.Text").init("Κατά τη συζήτηση") >
<cfset text.getTextInfo().setFontName("Arial Unicode MS")>
<cfset sec1.getParagraphs().add(text)>
<cfset demo_pdf.setUnicode()>
<cfset demo_pdf.save("c:\HelloWorld.pdf")>