From Bugzilla Helper:
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Description of problem:
/usr/sbin/isdndial seems to be the replacement of /usr/sbin/isdnup. It
seems to be a rewrite of that script too, which shows in a rather
trivial bug.

Version-Release number of selected component (if applicable):
isdn4k-utils-3.2-5.p1 (isdn4k-utils-3.2-13.p1.1 too)

How reproducible:
Always

Steps to Reproduce:
1. grep -n isdnup /usr/sbin/isdndial
    
Actual Results:
22:    echo $"Usage: isdnup <device name>" >&2
30:    echo $"Usage: isdnup <device name>" >&2

Expected Results:
grep -n isdndial /usr/sbin/isdndial
22:    echo $"Usage: isdndial <device name>" >&2
30:    echo $"Usage: isdndial <device name>" >&2

Additional info:
As I said: trivial ...