Yes, thats correct. GSM covers 85 to 90% market internationally. CDMA has about 10% market primarily in North America such as Canada and USA. Japan and South Korea's CDMA technology is totally different from the rest of the world. Even Sprint/Verizon/Atell Blackberry devices won't work in those Asian countries. In other words, Sprint BlackBerry models except 8830 and Tour also won't work in other GSM 250 plus countries.
It is likely for Deutsche Telekom AG to offer a bid on Sprint in several weeks from now.
Further link: CDMA vs GSM - Difference and Comparison - Diffen
One more thing. Sprint Corp. keeps on losing 500k to 900k customers per quarter since two years. Their market value is now $10 billion with debt of $21 billion.