It is also to be noted that Redsn0w does not support iOS 4.3.2 officially at this stage. So you might face some problems related to Cydia, like blank Cydia icon, after jailbreaking your device with Redsn0w.
All those users who rely on unlock must keep their devices away from the latest iOS 4.3.2 because Ultrasn0w may not be compatible with iOS 4.3.2.
Here is the guide to jailberak iOS 4.3.2 with Redsnow: [This guide is tested on iPhone 3GS]
Step 1:
Download iOS 4.3.2 for your device and restore it on your device using the latest iTunes.
Step 2:
Run Redsnow 0.9.6 RC 12 and when it asks for iPSW file, point it to iOS 4.3.1 instead of iOS 4.3.2.
Step 3:
Select “Install Cydia†option.
Step 4:
Put your device into DFU mode by following the onscreen instructions.
Now sit back and let Redsow do its work. After few minutes your device will restart automatically. Launch Cydia from Springboard and install your favorite tweaks.
Downloads:
Download Redsnow
Download iOS 4.3.2
Download iOS 4.3.1
images from [ShoutPedia]