Audio Ease has updated Altiverb to v5.4.9. They also recently released a new set of impulses of Kammermusiksaal, Berlin for registered users.

Changes in v5.4.9:

• [VST] Tails properly cleared when resuming playback from stopped state (Wavelab, Sequoia, Samplitude, and others).
• [VST] Compatible with Cubase 4.
• [VST] Remembers correctly its saved IR.
• [VST] Fixed problem with certain V-STack/audio interface combinations.
• [PT] some improvements to RTAS buffer system.