I see the same problem, Solaris 10 (Sparc), Perl 5.8.4, IPC::Run 0.82
t/pty..............# IO::Tty 1.08, IO::Pty 1.08
t/pty..............ok 9/32# Failed test (t/pty.t at line 147)
t/pty..............NOK 10# got: 'HELLO
# hello
# '
# expected: '(?i-xsm:^(?:hello\r?\n){2}(?!\n)$)'
t/pty..............ok 11/32# Failed test (t/pty.t at line 153)
t/pty..............NOK 12# got: 'HELLO
# hello
# WORLD
# world
# '
# expected: '(?i-xsm:^(?:hello\r?\n){2}(?:world\r?\n){2}(?!\n)$)'
t/pty..............ok 16/32# Failed test (t/pty.t at line 170)
t/pty..............NOK 17# got: 'hello
# '
# expected: '(?-xism:^hello\r?\n(?!\n)$)'
t/pty..............ok 19/32# Failed test (t/pty.t at line 178)
# got: 'hello
# world
# '
t/pty..............NOK 20# expected: '(?-xism:^hello\r?\nworld\r?\n(?!\n)$)'
t/pty..............ok 25/32# Failed test (t/pty.t at line 198)
t/pty..............NOK 26# got: 'hello
# hello
# HELLO
# hello
# '
# expected: '(?i-xsm:^(?:hello\r?\n){3}(?!\n)$)'
t/pty..............ok 27/32# Failed test (t/pty.t at line 204)
t/pty..............NOK 28# got: 'hello
# hello
# HELLO
# hello
# world
# world
# WORLD
# world
# '
# expected: '(?i-xsm:^(?:hello\r?\n){3}(?:world\r?\n){3}(?!\n)$)'
t/pty..............ok 32/32# Looks like you failed 6 tests of 32.
t/pty..............dubious
Test returned status 6 (wstat 1536, 0x600)
DIED. FAILED tests 10, 12, 17, 20, 26, 28
Failed 6/32 tests, 81.25% okay