diff --git a/src/frontend/numparam/general.h b/src/frontend/numparam/general.h
index 208ad8487..aa7eeb6c7 100644
--- a/src/frontend/numparam/general.h
+++ b/src/frontend/numparam/general.h
@@ -17,5 +17,6 @@ void cadd(SPICE_DSTRINGPTR s, char c);
 
 bool alfa(char c);
 bool alfanum(char c);
+bool alfanumps(char c);
 
 int yes_or_no(void);
diff --git a/src/frontend/numparam/mystring.c b/src/frontend/numparam/mystring.c
index 251cf2b4b..fa9e67092 100644
--- a/src/frontend/numparam/mystring.c
+++ b/src/frontend/numparam/mystring.c
@@ -149,3 +149,11 @@ alfanum(char c)
 {
     return alfa(c) || ((c >= '0') && (c <= '9'));
 }
+
+
+/* Additionally '-' allowed in subckt name if ps compatible */
+bool
+alfanumps(char c)
+{
+    return alfa(c) || ((c >= '0') && (c <= '9')) || c == '-';
+}
diff --git a/src/frontend/numparam/spicenum.c b/src/frontend/numparam/spicenum.c
index cd79d133f..ee4eddc13 100644
--- a/src/frontend/numparam/spicenum.c
+++ b/src/frontend/numparam/spicenum.c
@@ -28,6 +28,7 @@ Todo:
 
 #include "ngspice/fteext.h"
 #include "ngspice/stringskip.h"
+#include "ngspice/compatmode.h"
 
 #ifdef SHARED_MODULE
 extern ATTRIBUTE_NORETURN void shared_exit(int status);
@@ -185,8 +186,12 @@ findsubname(dico_t *dico, SPICE_DSTRINGPTR dstr_p)
             char *t;
             entry_t *entry;
             /* check for known subckt name */
-            for (t = p; alfanum(*t); t++)
-                ;
+            if (inp_compat_mode == COMPATMODE_PS)
+                for (t = p; alfanumps(*t); t++)
+                    ;
+            else
+                for (t = p; alfanum(*t); t++)
+                    ;
             spice_dstring_reinit(&name);
             pscopy(&name, p, t);
             entry = entrynb(dico, spice_dstring_value(&name));