It turns out that there's a pretty simple solution. Use the Apple Modem 2400 CCL from ARA 1.0. It works fine, and we have verified it.
We tested both ARA Personal Server 2.0 and 2.0.1 with a Macintosh Portable and reproduced your problem. The solution above resolves this problem for both ARA PS 2.0 and 2.0.1. We have reported your problem, and we're awaiting resolution.
Article Change History:
03 Jun 1994 - Added information on ARA 2.0.1 to article.
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