Cannot install most of Cydia's tweaks

[iDonev]

I just got a new 3GS (sold my old one half a year ago) and found myself in quite the predicament - most of my favorite tweaks and apps won't install!

My old phone was running extremely smoothly on 4.0.1, jailbroken by jailbreakme.com. Everything was running just fine back then. Now my new phone is running 4.3.3 with 06.15.00 baseband. And I get all manner of weird stuff from Cydia.

Here are a few examples of failed apps:

MyWi 4.0:
Depends iOS Firmware< 4.0
Depends IntelliStatusBarIcons>=0.91

Infinidock:
Depends IconSupport
Depends iOS Firmware >=3.0

SBSetting:
Depends iOS Firmware <4.0
Depends Activator >= 1.3.2

AndroidLock XT:
Depends iOS Firmware <3.2

All of those premium apps were purchased legally and worked just fine on 4.0.1.

Any ideas on how to fix this problem?