Hi Usman,
It might work but it will be unsupported since the Blackberry browser is not part of the supported ones for clientless WebVPN on IOS.
If Lotus uses a lot fo Javascript, I wouldn't put too much hope in it though.
Regarding the alternative SSL-VPN access means, it would work with AnyConnect but there is only a version of the client for Windows Mobile and for iPhone and it can only connect to an ASA firewall and not to a router so again, no luck here...
For a reference on the supported platforms/browsers, please see http://www.cisco.com/en/US/partner/prod/collateral/iosswrel/ps6537/ps6586/ps6657/product_data_sheet0900aecd80405e25.html
Regards,
Nicolas