diff --git a/src/acls.c b/src/acls.c

index 3f40541..e5a32a4 100644

--- a/src/acls.c

+++ b/src/acls.c

@@ -182,7 +182,7 @@ struct acluser **up;

 #endif

   (*up)->u_Esc = DefaultEsc;

   (*up)->u_MetaEsc = DefaultMetaEsc;

-  strncpy((*up)->u_name, name, 20);

+  strncpy((*up)->u_name, name, MAXLOGINLEN);

   (*up)->u_password = NULL;

   if (pass)

     (*up)->u_password = SaveStr(pass);

@@ -318,8 +318,8 @@ struct acluser **up;

     return UserAdd(name, pass, up);

   if (!strcmp(name, "nobody"))		/* he remains without password */

     return -1;

-  strncpy((*up)->u_password, pass ? pass : "", 20);

-  (*up)->u_password[20] = '\0';

+  strncpy((*up)->u_password, pass ? pass : "", MAXLOGINLEN);

+  (*up)->u_password[MAXLOGINLEN] = '\0';

   return 0;

 }

 #endif

diff --git a/src/acls.h b/src/acls.h

index 907e953..42c7c18 100644

--- a/src/acls.h

+++ b/src/acls.h

@@ -78,7 +78,7 @@ struct plop

 typedef struct acluser

 {

   struct acluser *u_next;		/* continue the main user list */

-  char u_name[20+1];		/* login name how he showed up */

+  char u_name[MAXLOGINLEN + 1];		/* login name how he showed up */

   char *u_password;		/* his password (may be NullStr). */

   int  u_checkpassword;		/* nonzero if this u_password is valid */

   int  u_detachwin;		/* the window where he last detached */

diff --git a/src/comm.c b/src/comm.c

index 5f4af8a..7705fcb 100644

--- a/src/comm.c

+++ b/src/comm.c

@@ -36,6 +36,7 @@

  */

 #include "config.h"

+#include "os.h"

 #include "acls.h"

 #include "comm.h"

diff --git a/src/display.h b/src/display.h

index b1ab748..a433e6d 100644

--- a/src/display.h

+++ b/src/display.h

@@ -73,7 +73,7 @@ struct display

   struct win *d_other;		/* pointer to other window */

   int   d_nonblock;		/* -1 don't block if obufmax reached */

 				/* >0: block after nonblock secs */

-  char  d_termname[40 + 1];	/* $TERM */

+  char  d_termname[MAXTERMLEN + 1];	/* $TERM */

   char	*d_tentry;		/* buffer for tgetstr */

   char	d_tcinited;		/* termcap inited flag */

   int	d_width, d_height;	/* width/height of the screen */

diff --git a/src/os.h b/src/os.h

index 5c17c83..bc71c97 100644

--- a/src/os.h

+++ b/src/os.h

@@ -521,3 +521,8 @@ typedef struct fd_set { int fds_bits[1]; } fd_set;

  */

 #define IOSIZE		4096

+/* Changing those you won't be able to attach to your old sessions

+ * when changing those values in official tree don't forget to bump

+ * MSG_VERSION */

+#define MAXTERMLEN  50

+#define MAXLOGINLEN 256

diff --git a/src/process.c b/src/process.c

index 7817ac8..a3c2e3d 100644

--- a/src/process.c

+++ b/src/process.c

@@ -2649,9 +2649,9 @@ int key;

       s = NULL;

       if (ParseSaveStr(act, &s))

 	break;

-      if (strlen(s) >= 20)

+      if (strlen(s) >= MAXTERMLEN)

 	{

-	  OutputMsg(0, "%s: term: argument too long ( < 20)", rc_name);

+     OutputMsg(0, "%s: term: argument too long ( < %d)", rc_name, MAXTERMLEN);

 	  free(s);

 	  break;

 	}

diff --git a/src/screen.c b/src/screen.c

index cd0c71b..7a21762 100644

--- a/src/screen.c

+++ b/src/screen.c

@@ -995,10 +995,10 @@ char **av;

   if (home == 0 || *home == '\0')

     home = ppp->pw_dir;

-  if (strlen(LoginName) > 20)

+  if (strlen(LoginName) > MAXLOGINLEN)

     Panic(0, "LoginName too long - sorry.");

 #ifdef MULTIUSER

-  if (multi && strlen(multi) > 20)

+  if (multi && strlen(multi) > MAXLOGINLEN)

     Panic(0, "Screen owner name too long - sorry.");

 #endif

   if (strlen(home) > MAXPATHLEN - 25)

diff --git a/src/screen.h b/src/screen.h

index 1a388e3..30ecefb 100644

--- a/src/screen.h

+++ b/src/screen.h

@@ -202,32 +202,32 @@ struct msg

 	  int nargs;

 	  char line[MAXPATHLEN];

 	  char dir[MAXPATHLEN];

-	  char screenterm[20];	/* is screen really "screen" ? */

+     char screenterm[MAXTERMLEN];	/* is screen really "screen" ? */

 	}

       create;

       struct

 	{

-	  char auser[20 + 1];	/* username */

+     char auser[MAXLOGINLEN + 1];	/* username */

 	  int apid;		/* pid of frontend */

 	  int adaptflag;	/* adapt window size? */

 	  int lines, columns;	/* display size */

 	  char preselect[20];

 	  int esc;		/* his new escape character unless -1 */

 	  int meta_esc;		/* his new meta esc character unless -1 */

-	  char envterm[40 + 1];	/* terminal type */

+     char envterm[MAXTERMLEN + 1];	/* terminal type */

 	  int encoding;		/* encoding of display */

 	  int detachfirst;      /* whether to detach remote sessions first */

 	}

       attach;

       struct 

 	{

-	  char duser[20 + 1];	/* username */

+     char duser[MAXLOGINLEN + 1];	/* username */

 	  int dpid;		/* pid of frontend */

 	}

       detach;

       struct 

 	{

-	  char auser[20 + 1];	/* username */

+     char auser[MAXLOGINLEN + 1];	/* username */

 	  int nargs;

 	  char cmd[MAXPATHLEN];	/* command */

 	  int apid;		/* pid of frontend */

diff --git a/src/socket.c b/src/socket.c

index 1f04284..32c5047 100644

--- a/src/socket.c

+++ b/src/socket.c

@@ -1528,7 +1528,7 @@ static void PasswordProcessInput __P((char *, int));

 struct pwdata {

   int l;

-  char buf[20 + 1];

+  char buf[MAXLOGINLEN + 1];

   struct msg m;

 };