Standard PDF fonts use several single byte encodings internally (see PDF Reference, Sixth Edition, version 1.7 Appendix D for details). They are generally equal to Latin1 character set (except Symbol and ZapfDingbats fonts).
Zend_Pdf uses CP1252 (WinLatin1) for drawing text with standard
Text still can be provided in any other encoding, which must be specified if it differs from a current locale. Only WinLatin1 characters will be actually drawn.
Example 673. Combining font embedding options
$font = Zend_Pdf_Font::fontWithName(Zend_Pdf_Font::FONT_COURIER);
->drawText('Euro sign - €', 72, 720, 'UTF-8')
->drawText('Text with umlauts - à è ì', 72, 650, 'UTF-8');