diff --git a/docs/changelog.rst b/docs/changelog.rst
index 14f86e77..1d8deb92 100644
--- a/docs/changelog.rst
+++ b/docs/changelog.rst
@@ -21,6 +21,7 @@ To avail of fixes in an unreleased version, please download a ZIP file
 Unreleased
 ----------
 
+* :gh:issue:`950` Fix Solaris/Illumos/SmartOS compatibility with become
 * :gh:issue:`1087` Fix :exc:`mitogen.core.StreamError` when Ansible template
   module is called with a ``dest:`` filename that has an extension
 * :gh:issue:`1110` Fix :exc:`mitogen.core.StreamError` when Ansible copy
diff --git a/mitogen/parent.py b/mitogen/parent.py
index 2a43cad2..2ed7e8ba 100644
--- a/mitogen/parent.py
+++ b/mitogen/parent.py
@@ -147,6 +147,8 @@ LINUX_TIOCGPTN = _ioctl_cast(2147767344)
 LINUX_TIOCSPTLCK = _ioctl_cast(1074025521)
 
 IS_LINUX = os.uname()[0] == 'Linux'
+IS_SOLARIS = os.uname()[0] == 'SunOS'
+
 
 SIGNAL_BY_NUM = dict(
     (getattr(signal, name), name)
@@ -411,7 +413,7 @@ def _acquire_controlling_tty():
         # On Linux, the controlling tty becomes the first tty opened by a
         # process lacking any prior tty.
         os.close(os.open(os.ttyname(2), os.O_RDWR))
-    if hasattr(termios, 'TIOCSCTTY') and not mitogen.core.IS_WSL:
+    if hasattr(termios, 'TIOCSCTTY') and not mitogen.core.IS_WSL and not IS_SOLARIS:
         # #550: prehistoric WSL does not like TIOCSCTTY.
         # On BSD an explicit ioctl is required. For some inexplicable reason,
         # Python 2.6 on Travis also requires it.
@@ -479,7 +481,8 @@ def openpty():
 
     master_fp = os.fdopen(master_fd, 'r+b', 0)
     slave_fp = os.fdopen(slave_fd, 'r+b', 0)
-    disable_echo(master_fd)
+    if not IS_SOLARIS:
+        disable_echo(master_fd)
     disable_echo(slave_fd)
     mitogen.core.set_block(slave_fd)
     return master_fp, slave_fp