diff --git a/lib/rb-readline/rbreadline.rb b/lib/rb-readline/rbreadline.rb
index 3dc3d70fc9..f46d348f43 100644
--- a/lib/rb-readline/rbreadline.rb
+++ b/lib/rb-readline/rbreadline.rb
@@ -774,7 +774,7 @@ module RbReadline
    @rl_num_chars_to_read = 0
 
    # Line buffer and maintenence.
-   @rl_line_buffer = nil
+   @rl_line_buffer = ""
 
    # Key sequence `contexts'
    @_rl_kscxt = nil
@@ -4845,7 +4845,7 @@ def rl_delete_text(from, to)
          text = nil
       end
       @rl_end -= diff
-      @rl_line_buffer[@rl_end] = 0.chr
+      @rl_line_buffer[@rl_end,1] = 0.chr
       return (diff)
    end