I wanted to import a font which has all the Greek characters
OS X already has everything for Greek, no need to import a font, Lucida Grande does it. OS X/Pages, unlike Appleworks, use Unicode, which means you no longer switch fonts to switch scripts, but activate a keyboard layout or use the Character Palette (edit > special characters) instead. You can activate a Greek layout in system prefs/international/input menu.
For more on Greek:
http://homepage.mac.com/thgewecke/TypingGreek.html
Just ask if you have any problems doing Greek input from Character Palette or the Greek keyboard.