Date/Time and Time Zone Settings: BEWARE!

Today I checked my BlackBerry Pearl 8130 and BlackBerry Curve 8330 and discovered that their times differed by several minutes. How could this be? I had both set to synchronize with the same Verizon Wireless network. I double-checked the settings, and was correct in my assumption. So, what went wrong? Are you someone who critically depends on your phone's time ...