JOELWNELSON  I've used 1Password with Safari in Leopard daily since Leopard came out. There were some issues for a couple days but it's been smooth sailing since then.  
(Version 2.5.9)

DTEARE  Send us an email and we'll get you up and running in a few minutes. We've had thousands of Leopard users using 1Password for months now.

If you send us a diagnostics report we can figure it out and help more. To send us a report, select Help > Troubleshooting > Send Diagnostics from the main 1Password application. Be sure to include the description you gave in your original problem description so that we can "connect the dots".  
(Version 2.5.9)

MACDRIVER  All I get is the "cant decript" message all other browsers are fine. Nothing seems to fix it. But I must add there seems to be many more issues with 10.5 on my mac pro 4core 3g then any of the other 4 machines I have it installed on (except for mail it sucks on all of them). Many things are absolutely awful with respect to reliability. Reminds me of the early days of sys 8 and sys 9 more fixing than using  
(Version 2.5.9)

DTEARE  If you send those diagnostics we might be able to help more.

Leopard has been an adventure as Apple's OS X Keychain Services have had many issues since the introduction of the new code signing feature in Leopard. It sounds like it could be the case here.  
(Version 2.5.9)

MACDRIVER  "[6080] Fri Jan 25 06:59:42 200| Failed to decrypt object (-25293): www.mac.com (macdriver@mac.com)/4930F831C3E04B6186A62241231B8C06

[6080] Fri Jan 25 06:59:43 200| Exception caught in (/Users/roustem/Projects/onepasswd_ext/BrowserPlugins/PluginLib/BrowserModel/BrowserDocument.mm:695): Failed to decrypt object (-25293): www.mac.com (macdriver@mac.com)/4930F831C3E04B6186A62241231B8C06"

I deleted the input bundel as noted in one members from /library as noted in on users comments. no different except 1password now not avaialble to any browser and reinstalling app, deleting pref dose not seem to get the input bundel back..

Saw interesting note in counsel message that it didnt like safari running in the rosetta mode (recomended if you want flash compatibility by adobe in certian web sites) took safari out of rosetta mode and decript issue gone but 1 password still no available to any browsers. clicked the icon install in 1password preferences , no change, deleted 1password preferences, no change. Any ideas how to get 1password functionality with browsers back?  
(Version 2.5.9)

DTEARE  We literally have 50 or so known configuration issues. You have to send us the diagnostics as we look for these as well as send a ton of logs.

To send us a report, select Help > Troubleshooting > Send Diagnostics from the main 1Password application. Be sure to include the problem description.  
(Version 2.5.9)

MACDRIVER  got functionality back. When I deleted input bundle I left the folder there so it was fooled into thinking it didn't have to install the input bundle. Trashed 1pasword folder and it installed the input bundle and functionality cam back.

With safari back in the intel native mode ( not running in rosetta) the decript issue is gone and full functionality of 1pasword in safari is back

I withdraw my grumpyness about 1 password but still grumpy with apple and 10.5.

Others may note the incompatibility of rosetta on Intel with safari and 1password. Something learned today

thanks for your help  
(Version 2.5.9)

DTEARE  Great to hear you're up and running again!

Apple and 10.5 has been an adventure for everyone :)

Now that you're happy again, can you post a 5/5 review to compensate for this bad 1/5 one?  
(Version 2.5.9)