ANSI-C Quoting bug in hotspot.m4 during configure on SLES 10 and 11

I've encountered a strange configure problem with the new hotspot build system on SLES 10 and 11:

...
checking which variants of the JVM to build... server
configure: Unknown variant(s) specified: server
configure: error: The available JVM variants are: server client minimal core zero zeroshark custom
configure exiting with result code 1
...

The error seems nonsense since 'server' is a valid variant.
For debugging purpose I ran "bash -vx configure ..." and this revealed:

$GREP -Fvx "${VALID_JVM_VARIANTS// /$'\n'}" <<< "${JVM_VARIANTS// /$'\n'}"
++++ /usr/bin/grep -Fvx 'server$\nclient$\nminimal$\ncore$\nzero$\nzeroshark$\ncustom'
+++ INVALID_VARIANTS=server

The expected result would be:

$GREP -Fvx "${VALID_JVM_VARIANTS// /$'\n'}" <<< "${JVM_VARIANTS// /$'\n'}"
++++ /bin/grep -Fvx 'server
client
minimal
core
zero
zeroshark
custom'
+++ INVALID_VARIANTS=

Apparently, the ANSI-C Quoting (see http://www.gnu.org/software/bash/manual/html_node/ANSI_002dC-Quoting.html#ANSI_002dC-Quoting) for "${VALID_JVM_VARIANTS// /$'\n'}" went wrong. Instead of replacing Spaces by newlines, it wrongly replaced Spaces by $\n instead.

I tried to find the specific problem without success. There exist several bugs about ANSI-C Quoting in bash. I could reproduce the problem on SLES 10.3 with the builtin bash 3.1.17 and a self-built bash 4.3.0 and also on a SLES 11.3 with the builtin bash 3.2.51. It worked on a newer SLES 12.1 with bash 4.2.47. I couldn't reproduce the problem on RHEL, Ubuntu and Fedora.