Using a parameter in a command

I'm running Crystal Reports XI against an Oracle database. I created a command which initially used a static value for one of the where comparisons. Now I have created a parameter with static values and I want the command to make the comparison against the entered selection for the parameter. After searching the internet, I tried many variations but so far none of them work. HERe is the where clause from the command with the last thing I tried (a like statement):

WHERE U.INSTRUMENT_TYPE_CD IN ('Future EFP Unposted')

AND (U.TRADE_NUM = S.TRADE_NUM AND U.TRADE_NUM = A.TRADE_NUM AND U.TRADE_NUM = T.TRADE_NUM AND U.TRADE_NUM = X.TRADE_NUM)

AND (U.TRADE_NUM = TTU.TRADE_NUM)

AND (S.EXTERNAL_KEY = A.CASHFLOW_NUM AND S.ITEM_STATUS_IND = 1 AND S.REPLACED_ITEM_HDR_NUM IS NULL)

AND S.COST_TYPE_CD = 'Primary Settlement'

AND U.STRATEGY_NUM = O.STRATEGY_NUM

AND O.PROCESS_GROUP_CD like {?LOB}

AND O.PARENT_STRATEGY_NUM IN (1080,1078,1081,1084,1007,2343)

AND (I.IND_NAME = 'buy_sell_ind' AND U.BUY_SELL_IND = I.IND_VALUE)

AND S.LOCATION_NUM = L.LOCATION_NUM

AND U.COUNTERPART_COMPANY_NUM = C.COMPANY_NUM

AND T.BROKER_COMPANY_NUM = C1.COMPANY_NUM

AND U.TRADER_PERSON_NUM = P.PERSON_NUM

AND (X.EXCH_CONTRACT_NUM = E.EXCH_CONTRACT_NUM AND X.QUOTE_DEF_NUM = E.QUOTE_DEF_NUM)

AND U.MTM_QUOTE_DEF_NUM = Q.QUOTE_DEF_NUM

ORDER BY FUTURE_EXPIRATION_DT, RISK_PERIOD_CD, QUOTE_DEF_CD

The line in question is AND O.PROCESS_GROUP_CD like {?LOB}. I've treid equals and IN's for the like. I've tried {?@LOB}. This should be so easy. Where am I going wrong?

Any help would be appreciated.