Red Hat AS , DigiNeo 4 port, kermit works but wvdial doesn't

I have an ISDN TA 128 and a USR Sportster connected to ttyn1a and b respectively. If I ask kermit to set line and dial, it talks to the modem just fine. If I configure /etc/wvdial.conf accordingly for my ppp connection, irrespective of which modem I try and use, I get the error, “MODEM NOT RESPONDING”. I have tried referencing /dev/ttyn1a and /dev/dg/dgnc/ttyn1a with no luck.

setserial -g ttyn1a
returns
Cannot get serial info: Invalid argument

wvdialconf doesn’t scan ttyn1* but if I hard link ttyn1a to ttySn1a I get :

Scanning your serial ports for a modem.

ttyS0<*1>: ATQ0 V1 E1 – ATQ0 V1 E1 – ATQ0 V1 E1 – nothing.
Port Scan<*1>: S1 S2 S3 S4 S5 S6 S7 S8
Port Scan<*1>: S9 S10 S11 S12 S13 S14 S15 S16
Port Scan<*1>: S17 S18 S19 S20 S21 S22 S23 S24
Port Scan<*1>: S25 S26 S27 S28 S29 S30 S31 SA0
Port Scan<*1>: SA1 SA2 SC0 SC1 SC2 SC3 SI0 SI1
Port Scan<*1>: SI2 SI3 SI4 SI5 SI6 SI7 SI8 SI9
Port Scan<*1>: SI10 SI11 SI12 SI13 SI14 SI15 SR0 SR1
Port Scan<*1>: SR2 SR3 SR4 SR5 SR6 SR7 SR8 SR9
Port Scan<*1>: SR10 SR11 SR12 SR13 SR14 SR15 SR16 SR17
Port Scan<*1>: SR18 SR19 SR20 SR21 SR22 SR23 SR24 SR25
Port Scan<*1>: SR26 SR27 SR28 SR29 SR30 SR31 SR256 SR257
Port Scan<*1>: SR258 SR259 SR260 SR261 SR262 SR263 SR264 SR265
Port Scan<*1>: SR266 SR267 SR268 SR269 SR270 SR271 SR272 SR273
Port Scan<*1>: SR274 SR275 SR276 SR277 SR278 SR279 SR280 SR281
Port Scan<*1>: SR282 SR283 SR284 SR285 SR286 SR287
ttySn1a<*1>: ATQ0 V1 E1 – AT
ttySn1a<*1>: ATQ0 V1 E1 – ATQ0 V1 E1 – nothing.

Sorry, no modem was detected! Is it in use by another program?
Did you configure it properly with setserial?

Both modems work fine when connected to /dev/ttyS0. so I know modem and cables and also the lines are fine. Kermit works ok, so presumably the problem lies somewhere between the driver and the O/S, which is Red Hat Advanced Server 2.1AS. wvdial is version 1.41. Any ideas ?

Please contact Technical Support for an updated driver:

http://www.digi.com/support/eservice/eservicelogin.jsp

Or call (952) 912-3456