Error: Function <SNR>56_MultiByteStrlen already exists, add ! to replace it

Hello, I 'm getting these errors opening vim:

Error detected while processing /home/username/.vim/bundle/vim-latex-suite/plugin/imaps.vim:
line  809:
E122: Function <SNR>56_MultiByteStrlen already exists, add ! to replace it
line  827:
E122: Function <SNR>56_MultiByteStrpart already exists, add ! to replace it
Press ENTER or type command to continue

After I press ENTER vim opens normally and then the message only reappears when I install a new plugin. Should I be worried? Should I fix it somehow? How?

My ~/.vimrc is:

"NeoBundle Scripts-----------------------------
"Note: Skip initialization for vim-tiny or vim-small.
" installed running: curl https://raw.githubusercontent.com/Shougo/neobundle.vim/master/bin/install.sh | sh
if !1 | finish | endif

if has('vim_starting')
set nocompatible               " Be iMproved

" Required:
set runtimepath+=~/.vim/bundle/neobundle.vim/
endif

" Required:
call neobundle#begin(expand('~/.vim/bundle/'))

" Let NeoBundle manage NeoBundle
" Required:
NeoBundleFetch 'Shougo/neobundle.vim'

" My Bundles here:
" Refer to |:NeoBundle-examples|.
" Note: You don't set neobundle setting in .gvimrc!
"
NeoBundle 'bling/vim-airline'
NeoBundle 'gerw/vim-latex-suite'
NeoBundle 'scrooloose/nerdtree'
NeoBundle 'tpope/vim-surround'
NeoBundle 'scrooloose/syntastic'
NeoBundle 'kien/ctrlp.vim'
NeoBundle 'Lokaltog/vim-easymotion'
"NeoBundle 'Valloric/YouCompleteMe'
NeoBundle 'nathanaelkane/vim-indent-guides'
call neobundle#end()

" Required:
filetype plugin indent on

" If there are uninstalled bundles found on startup,
" this will conveniently prompt you to install them.
NeoBundleCheck

" Airline
set laststatus=2
set t_Co=256
let g:airline#extensions#tabline#enabled = 0
"let g:airline_powerline_fonts=1
"let g:airline_theme = 'molokai'
let g:airline_theme = 'powerlineish'
let g:airline_enable_branch = 1
"let g:airline_enable_syntastic  = 1

" LaTeX suite
" REQUIRED. This makes vim invoke Latex-Suite when you open a tex file.
filetype plugin on

" IMPORTANT: win32 users will need to have 'shellslash' set so that latex
" can be called correctly.
set shellslash

" IMPORTANT: grep will sometimes skip displaying the file name if you
" search in a singe file. This will confuse Latex-Suite. Set your grep
" program to always generate a file-name.
set grepprg=grep\ -nH\ $*

" OPTIONAL: This enables automatic indentation as you type.
filetype indent on

" OPTIONAL: Starting with Vim 7, the filetype of empty .tex files defaults to
" 'plaintex' instead of 'tex', which results in vim-latex not being loaded.
" The following changes the default filetype back to 'tex':
let g:tex_flavor='latex'

" Syntastic
let g:syntastic_check_on_open = 1
let g:syntastic_mode_map = { 'mode': 'active',
            \ 'active_filetypes': ['python'],
            \ 'passive_filetypes': [] }
let g:syntastic_cpp_check_header = 1
let g:syntastic_cpp_auto_refresh_includes = 1
let g:syntastic_python_checkers = ['pyflake']
let g:syntastic_tex_checkers = ['lacheck']

gerw / vim-latex-suite

Error: Function <SNR>56_MultiByteStrlen already exists, add ! to replace it #17